Select the correct answer.
An Al scientist placed an agent in a known environment. The agent observed changes in the environment. Soon, it began to take action
toward making a decision. What was the agent doing?
A. offline computation
B. online computation
OC. learning
OD. perceiving

Answers

Answer 1

According to the given condition, the agent doing the process of perceiving. Thus the correct answer is D.

What is perceiving?

Perceiving refers to the implementation of any concept based on learning, understanding, and observation of skills to make effective decisions.

In this situation, the agent has observed changes in the environment and based on his observation and analysis began to take action for decision making.

These perceiving nature helps to enhance the process of learning to seek improvement.

Therefore, option D reflects the perceiving nature of agent.

Learn more about skills, here:

https://brainly.com/question/9648460

#SPJ1


Related Questions

i) Convert 8GB to bits. Give the expression.

Answers

Answer:

64 billion

Explanation:

1gb = 1 billion bytes

so 8gb = 8 billion bytes

then

1 byte= 8 bits

so 8 billion bytes = 8 × 8 billion bits, 64 billion bits

Which blu-ray standard defines rewritable disks?

Answers

The blu-ray standard that defines rewritable disks is BD-RE.

What is a rewritable disk?

It should be noted that a rewritable disk simply means an erasable disk that can be reused.

In this case, the blu-ray standard that defines rewritable disks is BD-RE. It is the recordable standard.

Learn more about disks on:

brainly.com/question/20381259

#SPJ12

the control plan is essential because it tells the

Answers

The control plan is essential because it tells the Process owners the way or how to sustain the project gains.

What is the aim of a control plan?

A control plan is known to be a kind of living document that states the methods to be used for quality control of any vital or critical inputs to transport outputs that can meet customer requirements.

Note that The control plan is essential because it tells the Process owners the way or how to sustain the project gains.

Learn more about control plan from

https://brainly.com/question/25453419

#SPJ11

Suppose a family has had a house fire in which they lost many photos, and they are worried about losing more if they have another. Which of the following is a reason this family may want to digitize their photos? Choose all that apply.

A: to make it easier to e-mail photos to friends

B: to maximize file space on their hard drive

C: to minimize risk of losing photos by backing them up in virtual space

D: to save space in their home

Answers

Answer:

C - Minimize the risk of future loss.

Explanation:

All four reasons listed are valid reasons to digitize family photos, but in this instance where this family has lost photos in a house fire before, minimizing the risk of losing photos in the future might be their primary goal.

What do both wireless lans (wlans) and wireless wans (wwans) rely on as the communication medium?

Answers

Wireless lans (WLANS) and wireless wans (wwans) rely on as the radio frequency spectrum communication medium.

What is Radio spectrum?

The radio spectrum is known to be an aspect of the electromagnetic spectrum that is said to have frequencies from 0 Hz to 3,000 GHz.

Note that Wireless lans (WLANS) and wireless wans (wwans) rely on as the radio frequency spectrum communication medium for their functions.

Learn more about WLANS from

https://brainly.com/question/26956118

#SPJ12

7.7% complete Question An aviation tracking system maintains flight records for equipment and personnel. The system is a critical command and control system that must maintain a global availability rate of 99%. The entire system is on a cloud platform that guarantees a failover to multiple zones within a region. In addition to the multi-zonal cloud failover, what other solution would provide the best option to restoring data and rebuilding systems if the primary cloud service becomes unavailable

Answers

The solution that would provide the best option to restoring data and rebuilding systems if the primary cloud service becomes unavailable is offline.

What is data?

It should be noted that data simply means the representation of facts ans concepts on a formalized manner.

In this case, the solution that would provide the best option to restoring data and rebuilding systems if the primary cloud service becomes unavailable is offline.

Learn more about data on:

brainly.com/question/4219149

#SPJ12

webrooming is when consumers physically inspect a product in a store to get a look and feel for it—and then buy it from an online store because it is cheaper to do so. true or false?

Answers

The statement that webrooming is when consumers physically inspect a product in a store to get a look and feel for it—and then buy it from an online store because it is cheaper to do so is false.

What is webrooming?

It should be noted that webrooming simply means the consumer practice for researching products online before buying theme in stores.

In this case, the main idea of webrooming isn't to buy it at stores because it's cheaper. Therefore, it's false.

Learn more about webrooming on:

brainly.com/question/14988432

#SPJ12

what statement can you use to divide a script into multiple batches?

Answers

The GO statement can be used to divide a script into multiple batches

How to determine the statement?

To divide a script, we make use of the GO statement or the GO command.

The GO statement has no syntax because it is not a keyword in SQL.

However, it is used by the SQL to create a group or batch of instructions that would be sent into the server

Read more about SQL at:

https://brainly.com/question/25694408

#SPJ11

what do you mean by computer ethics?​

Answers

Answer:

Computer ethics is a field of applied ethics that addresses ethical issues in the use, design and management of information technology and in the formulation of ethical policies for its regulation in society.

Take dismal Jack la floor italianizarla pues

Which wan connection types use digital communications over pots?

Answers

The WAN Connection that uses digital communications over pots is called; Digital Subscriber Line (DSL)

How to understand WAN (Wide area network)?

A wide area network(WAN) is defined as a telecommunications network that extends over a large geographic area.

Now, there are different means of transmitting these WAN networks but the connection type that uses digital communication over pots is called Digital Subscriber Line (DSL). This is because it digitally transmits data that is sent over the POTS copper wire infrastructure using Point–to–point (PTP) technology which experiences little to no congestion.

Read more about Wide area Network at; https://brainly.com/question/8118353

#SPJ12

Which feature on a cisco router permits the forwarding of traffic for which there is no specific route?

Answers

The feature on a cisco router permits the forwarding of traffic for which there is no specific route is a default static route.

What is a router?

A router simply means a network that used to provide access to the internet of a private computer network.

Here, the feature on a cisco router permits the forwarding of traffic for which there is no specific route is a default static route.

Learn more about router on:

brainly.com/question/24812743

#SPJ12

A for statement contains three expressions: initialization, test, and:

Answers

A for statement contains three expressions and these are:

InitializationTestUpdate

What is a for statement?

A for statement can be defined as a type of statement that is written by a computer programmer to repeat an action or event in a software program for a specific number of time.

In Computer programming, a for statement contains three expressions and these include the following:

InitializationTestUpdate

Read more on statements here: https://brainly.com/question/18736215

#SPJ12

What is open source software​

Answers

Answer:

Open Source Software

Explanation:

Open-source software is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open-source software may be developed in a collaborative public manner.

Answer:

open so software is an computer software that is reliance in which copyright holding reference uses the rights use study change and disturb this software and it so scold to anyone for any propose also open source software maybe diplobed in collaborative public manner

Explanation:

helpful

The programming process consists of several steps, which include:

Answers

The programming process consists of several steps, which include: Design, creation, testing, and debugging.

What are the steps in programming process?

The programming process is also made up of:

Defining the problem.Planning the solution.Coding the program.Testing the program.Documenting the program

Note also that The programming process consists of several steps, that include: Design, creation, testing, and debugging.

Learn more about programming process from

https://brainly.com/question/22654163

#SPJ12

When you coordinate tasks by email, you show respect for the recipient's time by:

Answers

When tasks are coordinated by email, you can show respect for the recipient's time by clearly stating your availability.

What is an e-mail?

An e-mail is an acronym for electronic mail and it can be defined as a software application (program) that is designed and developed to enable users send and receive both texts and multimedia messages over the Internet.

As good work ethics, when tasks are coordinated by e-mail, you can show respect for the recipient's time by clearly stating your availability and providing details about time frames.

Read more on e-mail here: https://brainly.com/question/15291965

#SPJ12

What should be used to prevent javascript from accessing a session id value?.

Answers

Cookies should be used to prevent javascript from accessing session-id values.

What are cookies?

Cookies are brief text messages that a website you visit sends to your browser.

Web browsers are instructed to only send cookies using encryption using the Secure cookie property.

The session ID can be taken from the user's browser cookies during storage, frequently via cross-site scripting. The session ID may be seen while it's being sent by listening in on network traffic.

Keep in mind that every request to the server includes a session ID. Using the cookie attribute of the Document object,

JavaScript is also capable of manipulating cookies. JavaScript has the ability to read, write, change, and remove cookies that are specific to the current web page.

Hence, cookies should be used to prevent javascript from accessing session-id values.

To learn more about the cookies refer to:

https://brainly.com/question/20263903

#SPJ1

For this PYTHON lab, we will use functions and imported functions to write a calculation program to do the following:


o Write a program that do the following unit conversion based on user menu selection: (use while

loop until the user enter ‘99’ selection to Quit)

1. Calculate Interest Rate

2. Calculate Mortgage

99 Quit


If user choice selection 1, then calculate interest rate. Modify your interest rate lab program

to be a function. Save this program to simple_interest.py filename in the current lab folder.

Use import to include the function in your main program.

o If user choice selection 2, then calculate mortgage. For this, you need to write a python

program function that will calculate mortgage payment. Save the program to mortgage.py

filename. You can modify the interest program with the following formulate:

1. How to calculate mortgage payment: (You MUST use the following test cases)

 Assume loanAmount = $100,000

 Assume interestRate = 3.25%

 Assume loanTerm = 15 years

 Then formula for mortgage calculation is:

monthlyRate = (interestRate / 100) / 12

numPayments = loanTerm * 12

monthlyPayment = loanAmount * monthlyRate \

* pow((1 + monthlyRate), numPayments) \

/ (pow((1 + monthlyRate),numPayments) - 1)

totalPayment = monthlyPayment * (loanTerm * 12)

interestPaid = totalPayment - loanAmount


 monthlyPayment would be: $702.67

 totalPayment would be: $126,480.38

 interestPaid would be: $26,480.38

PLEASE ANSWER WILL DO ANYTHING WILL MARK BRAINLIEST

Answers

Using the computational language in python it is possible to write a code that does the following unit conversion based on user menu selection:

Writing code in python:

def simple_interest(principal,rate,times,year):

       return principal + principal*(rate/times)*(times*year)/100.0

import simple_interest as si

from datetime import datetime

print("CNET-142: Ron Sha, Lab Menu Function\n",datetime.now())

def simpleInterest():

   print("\nCalulating Simple Interest")

   while True:

       principal = float(input("Enter the starting pricipal, <= 0 to quit: "))

       if principal > 0:

           rate = float(input("Enter the annual interest rate: "))

           times = float(input("How many times per year is the interest compounded? "))

           year = float(input("For how many years will the account earn interest? "))

           totalamount = si.simple_interest(principal, rate, times, year)

           print("At the end of ",year," years you will have $ ",totalamount," with interest earned $ ",totalamount-principal)

       else:

           print("Exiting Simple Interest program...")

           break

def mortagePayment():

   while True:

       loanAmount = float(input("Enter the loan amount, 0 to quit: "))

       if loanAmount>0:

           interestRate = float(input("Enter the loan interest rate: "))

           loanTerm = float(input("Enter the loan term (number of years): "))

           monthlyRate = (interestRate/100)/12

           numPayments = loanTerm*12

           monthlyPayment = round(loanAmount * (monthlyRate*pow((1+monthlyRate), numPayments))/ (pow((1+monthlyRate), numPayments)-1),2)

           totalPayment = round(monthlyPayment*(loanTerm*12),2)

           interestPaid = round(totalPayment - loanAmount,2)

           print("For the loan Amount of $",loanAmount," for ",loanTerm," years with interest rate of ",interestRate," %")

           print("The monthly payment is $",monthlyPayment)

           print("Total amount paid for this loan is $",totalPayment)

           print("Total interest paid for this loan is $",interestPaid)

       else:

           break  

def menuChoice():

   menuchoice = int(input("Select one of the command number above: "))

   if menuchoice == 1:

       simpleInterest()

       return

   elif menuchoice == 2:

       mortagePayment()

       return

   elif menuchoice == 99:

       print("Have a nice day...")

       global flag

       flag = 0

       return

   else:

       print("Error: command not recognised")

       menuChoice()

flag = 1

while flag == 1:

   print("\n------------------------------------------------------")

   print("1\tCalculate Simple Interest\n2\tCalculate Mortage Payment\n99\tQuit the Program")

   print("------------------------------------------------------\n")

   menuChoice()

See more about python at brainly.com/question/18502436

#SPJ1

You hide three worksheets in a workbook and need to unhide them. What is an accurate statement about this process?

Answers

The  accurate statement about this process is that "The person must unhide each worksheet separately".

How do you unhide multiple sheets in Excel?

To unhide multiple sheets, one can:

Right-click the Sheet tab at the bottom, and then click on  Unhide. Then also click all together the Shift + Up/Down Arrow keys to click multiple (or all) worksheets, and then click OK.

Note that The  accurate statement about this process is that "The person must unhide each worksheet separately".

Learn more about worksheets  from

https://brainly.com/question/25130975

#SPJ12

An aggregate function is _____. A. a function that calculates a statistic such as a subtotal or average B. a mathematical expression, such as [Qty]*[UnitsSold] C. a way to group records, such as by state or postal code D. a way to test the accuracy of data

Answers

Answer:

A. a function that calculates a statistic such as a subtotal or average.

A/An is useful in comparing data values from populations with different means and standard deviations.

Answers

A useful tool in comparing data values from populations with different means and standard deviations is z-score.

What is a Z-score?

This is known to be a kind of numerical measurement that tells a value's association to the mean of a group of values.

The Z-score is said to be measured in regards to standard deviations that arises from the mean.

Note that A useful tool in comparing data values from populations with different means and standard deviations is z-score.

Learn more about z-score from

https://brainly.com/question/25638875

#SPJ11

algorithm to print the first 10 odd numbers​

Answers

Answer:

I have the code written in c++ but the logic will be the same you just have to change the syntax ( if you're writing different language)

Explanation:

please mark brainliest

When a cookie is created during a website visit, it is stored:

Answers

When a cookie is created during a website visit, it is stored on the hard drive if the visitor's computer.

What is a cookie?

A cookie simply means the small blocks of data that are created by a web server.

In this case, when a cookie is created during a website visit, it is stored on the hard drive if the visitor's computer.

Learn more about cookie on:

brainly.com/question/1308950

#SPJ12

In what type of attack does the adversary leverage a position on a guest operating system to gain access to hardware resources assigned to other operating systems running in the same hardware environment

Answers

Answer:

VM escape attack

Explanation:

In a VM escape attack, the attacker exploits hypervisor vulnerabilities to gain control over resources reserved for other guest operating systems. Services operating on the guest may be exposed to the other attacks, but such attacks can only access data allotted to the same guest. In the event of a buffer overflow or directory traversal or the client in the case of cross-site scripting.

what is the minimum number of load balancers needed to configure active/active load balancing?

Answers

Answer:

2

Explanation:

The primary and secondary machines should both be actively handling connections to your virtual servers in order for active/active to entail having two load balancing appliances running concurrently. The second interpretation of active/active has to do with ones back end servers, which are all running and accepting connections behind the virtual service. This makes use of all of your available computing power for accepting connections.

The minimum number of load balancers needed to configure active/active load balancing is 2.

What are load balancers?

Load balancing is known to be a key networking solution that is often employed to share traffic across multiple servers in the case of server farm.

Note that The minimum number of load balancers needed to configure active/active load balancing is 2.

See full question below

What is the minimum number of load balancers needed to configure active/active load balancing?

- 2

- 4

- 1

- 3

Learn more about load balancers from

https://brainly.com/question/13088926

#SPJ11

QUESTION 9 OF 100
What does it means when you see a sign with an "X" and two
letters "R" sign posted on the roadside?

Answers

Answer:

it means go sleep on ur bed

jk

Answer:

the sign means "railroad"

Explanation:

A router is performing basic routing functions. What will be the third step in the transmission of a packet?

Answers

The third step in the transmission of a packet is known as a network layer.

What is a router?

It should be noted that a router is a device that connects two or more packets networks.

Here, the third step in the transmission of a packet is known as a network layer. It adds another header in what is received.

Learn more about router on:

brainly.com/question/24812743

#SPJ12

When a file is used by a program, there are three steps that must be taken:

Answers

The three steps that must be taken:

Open the file Process the fileClose the file

What is file opening?

The act of Opening a file is one that makes a a connection to exist between the file and the program.

Note that The three steps that must be taken:

Open the file Process the fileClose the file

Learn more about program from

https://brainly.com/question/1538272

#SPJ12

HURRY PLS
polina is a system architect and at the point in her current project where she must review the code at a high level to make sure it meets all the requirements. After that, which of the following groups will polina work with


A) the testing team

b)the CEO

Answers

Answer:

the testing team

Explanation:

because even though she may have fulfilled the requirements but she still need to test if it runs perfectly or not

30 POINTS FOR THE CORRECT ANSWER
Ruben is volunteering as a reading helper with a kindergarten class in his hometown. He really likes all 24 of the students and wants to do something nice for them. He has decided to design a book for them as a gift. Ruben plans on drawing all his own illustrations and laying out the pages, but he wants each of their names to be interwoven into the story.

What are the different options Ruben could consider for printing his books? Choose a printing method and detail why it is the best choice for Ruben. Next, choose another printing method and detail why it is not the best choice for Ruben.

Answers

In the case above, Ruben  should consider the printing option below:

Offset litho printing.Digital Printing.Screen printing.

What is the best printing type for books?

The use of digital printing is known to be the best in the case with Ruben. It is said to be much more economical in terms of shorter print runs.

Note that Digital printing do have fast turnaround time and as such it is better for books.

Therefore, In the case above, Ruben  should consider the printing option below:

Offset litho printing.Digital Printing.Screen printing.

Learn more about printing from

https://brainly.com/question/145385

#SPJ1

Your friend just noticed his smartphone's battery is running low. Unfortunately, your friend isn't very knowledgeable about computers and smartphones, so he doesn't know what type of charging cable he needs. He knows his phone is running iOS 12. What kind of cable does your friend need to charge his phone

Answers

Answer:

Lightning

Explanation:

Apple Inc. designed and developed the Lightning computer bus and power connection. Apple mobile devices such as iPhones, iPads, and iPods use the Lightning connection to connect to host computers, external displays, cameras, USB battery chargers, and other accessories. Lightning is substantially smaller than its predecessor, with only 8 pins instead of 30.

Other Questions
The students in Mr. McIntyres class and the students in Mrs. Ramoss class were asked how many pets they each have. The dot plots below show the results.Mr. McIntyres ClassA dot plot titled Mister McIntyre's Class. A number line going from 0 to 5 is labeled Number of Pets. There are 5 dots above 0, 5 above 1, 4 above 2, 1 above 3, and 0 above 4 and 5.Mrs. Ramoss ClassA dot plot titled Misses Ramos's Class. A number line going from 0 to 5 is labeled Number of Pets. There is 1 dot above 0, 2 above 1, 2 above 2, 4 above 3, 3 above 4, 3 above 5.Which statement correctly compares the means of the data in the dot plots? Solve the following...6x - 5 = -9x -9 Cycle City charges an initial price of $15 plus $0.75 per house for bike rentals, which is represented by the expression 15 + 0.75h . Complete the statement to describe the terms... When independent stock transfer agents are not employed and the corporation issues its own stock and maintains stock records, canceled stock certificates should Multiple Choice Not be defaced but be segregated from other stock certificates and retained in a canceled certificates file. Be destroyed to prevent fraudulent reissuance. Be defaced to prevent reissuance and attached to their corresponding stubs. Be defaced and sent to the secretary of state. what was the rationale for creating the merit system of selecting judges Question 4 of 40Which of these is a correct expansion of (3x-2)(2x2+5)?OA. 3x 2x2 + 3x 5+2 2x +2.5B. 3x 2x2 + 3x.5+ (-2) 2x2 + (-2).5O C. 3x 2x+(-2) 2x + 2x.5+ (-2).5SUBMIT If g:x = 2x-3 4 find 9^-1 (-3) Why is the majority of the world dependent on the Middle East? How does the word shattered affect the tone of the excerpt? the word suggests a tragic tone. the word suggests a fearful tone. the word suggests a pathetic tone. the word suggests a nervous tone. A local customer service firm requires prospective employees to take an emotional intelligence test that measures their ability to monitor their emotions and others' emotions and use that information to guide their actions. The measure has high predictive validity for exemplary job performance. Which statement is likely true about new hires who score high on this measure A low-cost leadership strategy becomes competitively powerful when a. buyers of the product or service use the product or service in the same ways. b. the offerings of rival firms are essentially unique, different, and customized to end users. c. price competition among rivals is absent. d. buyers prefer that the products/services of competing sellers have widely varying attributes and prices. e. buyers have high switching costs. The laboratory test that measure the percentage by volume of packed red blood cells in a whole blood sample is known as a/an test. The coordinate grid shows points A through K. What point is a solution to the system of inequalities? y < 2x + 10 y < 1 over 2x 2 coordinate grid with plotted ordered pairs, point A at negative 5, 4 point B at 4, 7 point C at negative 2, 7 point D at negative 7, 1 point E at 4, negative 2 point F at 1, negative 6 point G at negative 3, negative 10 point H at negative 4, negative 4 point I at 9, 3 point J at 7, negative 4 and point K at 2, 3 I B A F Question 8(Multiple Choice Worth 1 points) (04.06 MC) In the graph, the area below f(x) is shaded and labeled A, the area below g(x) is shaded and labeled B, and the area where f(x) and g(x) have shading in common is labeled AB. Graph of two intersecting lines. One line g of x is solid and goes through the points negative 3, 0, negative 4, negative 1 and is shaded in below the line. The other line f of x is solid, and goes through the points 1, 1, 2, negative 1 and is shaded in below the line. The graph represents which system of inequalities? y 2x + 3 y x + 3 y 2x + 3 y x + 3 y 3x + 2 y x + 2 y > 2x + 3 y > x + 3 Question 9(Multiple Choice Worth 1 points) (04.06 LC) Choose the graph that represents the following system of inequalities: y 3x + 1 y 1 over 2x + 3 In each graph, the area for f(x) is shaded and labeled A, the area for g(x) is shaded and labeled B, and the area where they have shading in common is labeled AB. Graph of two intersecting lines. Both lines are solid. One line f of x passes through points negative 2, 2 and 0, 3 and is shaded above the line. The other line g of x passes through points 0, 1 and 1, negative 2 and is shaded above the line. Graph of two lines intersecting lines. Both lines are solid. One line g of x passes through points negative 2, 2 and 0, 3 and is shaded below the line. The other line f of x passes through points 0, 1 and 1, negative 2 and is shaded above the line. Graph of two intersecting lines. Both lines are solid. One line passes g of x through points negative 2, 2 and 0, 3 and i Which contributor is likely to be the cause of U.S. childrens inadequate fitness levels?Group of answer choicesChildren live a sedentary lifestyle.There is no national effort to increase the level of childrens fitness.Children eat too sporadically.Children eat a diet that is too dairy dependent. hich initiatives are pillars of the Lets Move! program? Select three options.increasing physical activityproviding more snack times in schoolscreating a healthy start for childrenempowering parents and caregiversproviding children with vitamin supplements please tell me the answer...due today Hellpppp Neeededd, How To SolveQuadratic Formula Equation To x +9x+8=0 A small island country has recently begun an initiative aimed at attracting more businesses to revitalize the economy. An increase in bed and breakfasts, resorts, casinos, hotels, and restaurants has created several jobs, as well as brought in more tourist dollars. However, the islands president isn't satisfied and has announced a special effort to attract small- to medium-size suppliers and manufacturers. Why do you think he wants to put additional emphasis on businesses that produce goods rather than provide services?Service jobs have higher salaries than manufacturing jobs.Manufacturers pay more in taxes.Manufacturing has the most significant multiplier effect.Service businesses conflict with manufacturing. Explain how alcohol affects the body and the brain 30 points!!!! Answer fastEXPERIMENT: MAGNETISM Bar Magnet 1. Place the bar magnet on a table. 2. Put a sheet of glass or plastic over the magnet. 3. Sprinkle the iron filings over the sheet evenly. 4. On a separate paper, sketch the magnet. Show the lines made by the iron filings. Horseshoe Magnet 5. Place a horseshoe magnet on the table. 6. Put a sheet of glass or plastic over the magnet. 7. Sprinkle the iron filings over the sheet. 8. On a separate paper, sketch the magnet. Show the lines made by the iron filings. N Pole to N Pole 9. Place two bar magnets N pole to N pole with an inch between them. 10. Put a piece of glass or plastic over the magnets. 11. Sprinkle the iron filings over the glass or plastic. 12. On a separate paper sketch the magnets. Show the lines made by the iron filings. N Pole to S Pole 13. Turn one of the bar magnets around so the magnets are N pole to S pole with an inch between. 14. Sprinkle the iron filings over the glass or plastic. 15. On a separate paper sketch the magnets. Show the lines made by the iron filings. From the information you have observed, determine the following: What rule of magnetism is illustrated by the lines of the iron filings in Step 12? What rule of magnetism is illustrated by the lines of the iron filings in Step 15? Why was glass or plastic used to separate the filings from the magnets in the experiments? Did the glass or plastic stop the passage of the magnetic lines of force? Did the iron filings almost or completely bridge the open end of the horseshoe magnet?