plssssss help state testing is coming up !!!

Answer:

$11.90

Step-by-step explanation:

11 and 9/10 converted to dollars and cents is 11.90

11 is 11 wholes, therefore it stays the same.

1/10 is equal to .10, so 9/10 is equal to .90.

SORRY IF THIS DOESN'T MAKE SENSE!

The length of side "r" in the triangle PQR is 70.75 m.

A triangle is a three-sided polygon, a basic shape in geometry. It is formed when three straight lines intersect at three points, creating interior angles that add up to 180 degrees. Triangles can be classified according to their sides, angles, and type, such as right-angled, equilateral, and isosceles. Triangles are often used in construction to form roofs, beams, and walls. They are also used in geometry and trigonometry to calculate distances, angles, and areas.

To calculate the length of "r" in a non-right-angled triangle, the Sine Rule can be used. The Sine Rule states that, for any triangle, the ratio of the length of a side to the sine of the opposite angle is the same for all sides.

In the triangle PQR, side "r" is the side opposite angleR. The sine of angleR is 0.53. Therefore, the ratio of the length of "r" to the sine of angleR is:

r/sin R = 37.5/0.53

r = 37.5/0.53 = 70.75 m.

Therefore, the length of side "r" in the triangle PQR is 70.75 m.

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The available credit on Shareese's credit card is $$1432.75.

To find the available credit on Shareese's credit card, we need to subtract her new balance from her credit line.

Shareese's credit line is $3,000 and her new balance is $1,567.25. Therefore, the available credit on her card is:

= $3,000 - $1,567.25

= $1,432.75

Therefore, the available credit on Shareese's credit card is $2,000.

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The marginal revenue function is the derivative of the revenue function with respect to the quantity x. Since revenue is equal to price times quantity, we can write the revenue function as R(x) = p(x)*x. Therefore, the marginal revenue function is:

dR/dx = dp/dx * x + p(x) * dx/dx

But dx/dx = 1, so we can simplify the above expression as:

dR/dx = dp/dx * x + p(x)

We are given the demand function p(x) = 150 - 80x - 35x^2, so we can find dp/dx by taking the derivative with respect to x:

dp/dx = -80 - 70x

Substituting this into the expression for the marginal revenue function, we get:

dR/dx = (-80 - 70x) * x + (150 - 80x - 35x^2)

Simplifying this expression, we get:

dR/dx = -35x^2 - 10x + 150

Therefore, the marginal revenue function is:

a) Odr/dx = 150x – 35x3 is not correct

b) Odr/dx = 150 – 160x – 105x2 is not correct

c) Odr/dx = 1650 - 700x2 – 35x3 is not correct

d) Odr/dx = 1800x - 700x2 is not correct

The correct answer is:

dR/dx = -35x^2 - 10x + 150

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The probability that the phone would last the entire trip of 45 hours is 2.28%

To calculate the probability that the phone would last the entire 45-hour trip:

We need to use the concept of standard deviation and assume that the usage time follows a normal distribution.

Using Excel, we can use the following formula to calculate the probability:

= NORM.DIST (x, mean, standard deviation, cumulative)

Where x is the value we want to test, the mean is the average usage time on a full charge (30 hours), and the standard deviation is 5 hours.

To calculate the probability that the phone will last the entire 45-hour trip,

we need to find the probability that the usage time is greater than or equal to 45 hours.

= NORM.DIST (45, 30, 5, TRUE)

This gives us a probability of 0.0228 or 2.28%. Therefore, there is a very low probability that the phone will last the entire 45-hour trip.

In summary, the probability that the phone will last the entire 45-hour trip is 2.28% based on the assumption that the usage time follows a normal distribution with a mean of 30 hours and a standard deviation of 5 hours.

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Both sequences, HHHHHHHHHH and HTHTHTHTHT, are equally likely when flipping a coin ten times.

Each coin flip has an independent probability of 0.5 of landing heads or tails, so the probability of getting a sequence of ten heads in a row is (0.5)^10 = 0.0009766 or approximately 0.1%. Similarly, the probability of getting a sequence of five heads followed by five tails is (0.5)^10 = 0.0009766 or approximately 0.1%. Therefore, both sequences have the same probability of occurring, and neither is more likely than the other.

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The terminal side of a 540 degree angle in standard position will lie on the negative x-axis.

Standard Position: If an angle's vertex is at its origin and one of its rays is on the positive x-axis, it is in the standard position. The initial side and the terminal side are the names given to the rays along the x-axis.

In standard position, a 900-degree angle will have its initial side along the positive x-axis and its terminal side rotating by 900 degrees counterclockwise.

Since each full counterclockwise revolution compares to a point of 360 degrees, we can take away 360 degrees from 900 degrees to track down the same point inside one full turn:

900 degrees - 360 degrees = 540 degrees

Thus, a 900 degree angle in standard position is equivalent to a 540 degree angle in standard position.

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The probability that the time between consecutive customers is less than 15 seconds is approximately 0.29 or 29.02% (rounded to two decimal places).

To calculate the probability that the time between consecutive customers is less than 15 seconds using the Exponential distribution with a mean of 0.73 minutes, first convert 15 seconds into minutes.

15 seconds = 15/60 = 0.25 minutes

Next, use the Exponential distribution formula:

P(X ≤ x) = 1 - e^(-λx)

Here, λ is the rate parameter and is equal to 1/mean, which in this case is:

λ = 1/0.73 ≈ 1.37

Now, plug in the values into the formula:

P(X ≤ 0.25) = 1 - e^(-1.37 × 0.25) ≈ 1 - e^(-0.3425)

P(X ≤ 0.25) ≈ 1 - 0.7098 ≈ 0.2902

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The first 4 non-zero terms of the Taylor polynomial are f(x) = x - x²/2 + 2x³/3 - x⁴/4 + ...

What is the Taylor series?

The Taylor series is a mathematical representation of a function as an infinite sum of terms that are calculated from the values of the function's derivatives at a single point.

The nth term of the Taylor series for f(x) about x = a is given by:

f^n(a)/n!(x-a)ⁿ

Here, we need to find the first 4 non-zero terms of the Taylor series for f(x) = ln(x+1) about x=0.

f(x) = ln(x+1)

f'(x) = 1/(x+1)

f''(x) = -1/(x+1)²

f'''(x) = 2/(x+1)³

f''''(x) = -6/(x+1)⁴

Now, we can find the Taylor series for f(x) about x=0 as follows:

f(0) = ln(0+1) = 0

f'(0) = 1/(0+1) = 1

f''(0) = -1/(0+1)² = -1

f'''(0) = 2/(0+1)³ = 2

f''''(0) = -6/(0+1)⁴ = -6

So, the first 4 non-zero terms of the Taylor series for f(x) = ln(x+1) about x=0 are:

0 + 1x - 1x²/2 + 2x³/3 - 6x⁴/4!

Simplifying, we get:

f(x) = x - x²/2 + 2x³/3 - x⁴/4 + ...

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The output of print(1+3/2*2) is 5.0

This is because the order of operations in arithmetic dictates that multiplication and division should be performed before addition and subtraction.

So, first 3/2 is evaluated which gives 1.5, then 1.5 is multiplied by 2 to give 3, and finally, 1 is added to 3 to get the result of 5.0. Hence, 5.0 will be printed by the print (1+3/2*2).

Note that the result is a floating-point number because division between two integers in Python 3. x always results in a float, even if the result is a whole number.

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The value of x is given as follows:

x = 2.

We are given two segments on the circle, and their lengths are given as follows:

The two segments represent chords on the circle, which are line segments connecting two points on the circumference of the circle.

As the two points are chords, they have the same length, and thus the value of x is obtained as follows:

8x - 3 = 2x + 9

6x = 12

x = 2.

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Events A and B are not independent as the probability of both events occurring together is not equal to the product of their individual probabilities.

Events A and B are considered independent if the occurrence of one event does not affect the probability of the other event occurring. In this case, the probability of event A occurring is 0.5, the probability of event B occurring is 0.7, and the probability of both events A and B occurring is 0.34. Since the probability of both events A and B occurring (0.34) is not equal to the product of the probabilities of each event occurring independently (0.5 * 0.7 = 0.35), Events A and B are not independent.

Therefore, Events A and B are not independent as the probability of both events occurring together is not equal to the product of their individual probabilities.

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The quotient of 9.2×10⁸ and 4.6×10⁴ expressed in scientific notation is 2.0×10⁴.

In scientific notation, commonly referred to as exponential notation, very big or very small quantities are expressed by employing powers of 10. in notation used in science. There are several uses for scientific notation. First of all, it enables us to write extremely huge or extremely small numbers in a condensed and readable style. For instance, the about 93,000,000 mile distance between the Earth and the Sun can be difficult to write and manage because it is such a huge quantity.

The quotient is obtained when we divide the two numbers as follows:

9.2×10⁸ ÷ 4.6×10⁴ = 20,000

20,000 = 2.0×10⁴

Hence, the quotient of 9.2×10⁸ and 4.6×10⁴ expressed in scientific notation is 2.0×10⁴.

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The test statistic for the hypotheses H₀: p = 0.31 vs H₁: p > 0.31, given 115 out of 365 community college students have a smartphone, is approximately 0.87.


1. Calculate the sample proportion (p-hat): p-hat = 115 / 365 = 0.3151.
2. Determine the null hypothesis proportion (p₀): p₀ = 0.31.
3. Calculate the standard error (SE) for the sample proportion using the null hypothesis proportion: SE = sqrt(p₀ * (1 - p₀) / n) = sqrt(0.31 * (1 - 0.31) / 365) ≈ 0.0282.
4. Calculate the test statistic (z) using the sample proportion, null hypothesis proportion, and standard error: z = (p-hat - p₀) / SE = (0.3151 - 0.31) / 0.0282 ≈ 0.87.

The test statistic is approximately 0.87, which will be used to determine if there is significant evidence to support the professor's claim.

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a. For this study, we should use a t-test because the population standard deviation is unknown, and the sample size is small (n=13).

b. The null and alternative hypotheses would be:
H0: μ = 81 (The average college student consumes the same amount of alcohol as the average American, 81 liters per year.)
H1: μ ≠ 81 (The average college student consumes a different amount of alcohol per year than the average American.)

To perform the t-test, follow these steps:

1. Calculate the t-value:
t = (sample mean - population mean) / (sample standard deviation / √sample size)
t = (65.8 - 81) / (24 / √13)
t = -15.2 / (24 / 3.606)
t = -15.2 / 6.656
t = -2.283

2. Determine the critical t-value for a two-tailed test at α=0.01 level of significance and 12 degrees of freedom (n-1):
Using a t-table or calculator, the critical t-value is approximately ±2.681.

3. Compare the calculated t-value to the critical t-value:
Since -2.283 is not more extreme (less than -2.681 or greater than 2.681), we fail to reject the null hypothesis (H0).

Conclusion: At the α=0.01 level of significance, there is not enough evidence to conclude that the average college student consumes a different amount of alcohol per year than the average American.

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The inequality ensures that Eddie does not exceed his budget of $15

The correct inequality to find how many miles Eddie can travel if he has $15 to spend is $1.75 + $0.25x ≤ $15 where x represents the number of miles Eddie can travel.

This is a inequality can be solved by subtracting $1.75 from both sides and then dividing by $0.25 and giving,

$0.25x ≤ $13.25 x ≤ 53

So, Eddie can travel up to 53 miles if he has $15 to spend on the taxicab, including the flat fee of $1.75 and the additional $0.25 charge per mile.

Hence, this inequality ensures that Eddie does not exceed his budget of $15.

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The derivative of f(x) = 244 using logarithmic differentiation is f'(x) = 0. To find f'(1), we plug in x = 1 and get f'(1) = 0.

This means that the slope of the tangent line to the graph of f(x) at x = 1 is 0, indicating a horizontal line.

Logarithmic differentiation is a technique used to find the derivative of a function by taking the natural logarithm of both sides of the equation, then differentiating implicitly. In this case, we have f(x) = 244, so ln(f(x)) = ln(244). Differentiating both sides with respect to x gives:

1/f(x) * f'(x) = 0

Simplifying, we get f'(x) = 0. This makes sense because the function f(x) is a constant function, which has a derivative of 0 at every point.

To find f'(1), we plug in x = 1 into f'(x) and get f'(1) = 0. This tells us that the slope of the tangent line to the graph of f(x) at x = 1 is 0, indicating a horizontal line.

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Big O represents the worst-case performance, Big Theta represents the average-case performance, and Big Omega represents the best-case performance of an algorithm.

Big O, Big Theta, and Big Omega are all notations used in computer science to describe the performance of algorithms, specifically their time complexity.

Each notation represents a different aspect of an algorithm's behavior:

1. Big O (O): Big O notation is used to express the upper bound of an algorithm's running time, meaning it describes the maximum number of operations an algorithm might take in the worst-case scenario. In other words, Big O represents the upper limit on how slow an algorithm can be.

2. Big Theta (Θ): Big Theta notation is used to describe the average-case running time of an algorithm. It represents both an upper and lower bound, meaning it gives a tight bound on the number of operations an algorithm takes in the average case. Essentially, Big Theta indicates the general performance of an algorithm.

3. Big Omega (Ω): Big Omega notation is used to express the lower bound of an algorithm's running time, meaning it describes the minimum number of operations an algorithm might take in the best-case scenario. In other words, Big Omega represents the lower limit on how fast an algorithm can be.

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The derivative formula for the function is f'(x) = 5(5x + 23)^4(5)(15x + 4) + (5x + 23)^5(15).

To find the derivative of the function f(x) = (5x + 23)^5(15x + 4), we will use the product rule. The product rule states that the derivative of two functions multiplied together is the derivative of the first function times the second function plus the first function times the derivative of the second function.

Let u(x) = (5x + 23)^5 and v(x) = (15x + 4).

To find u'(x), we use the chain rule: u'(x) = 5(5x + 23)^4(5), where 5 is the derivative of the inner function 5x + 23.

To find v'(x), we take the derivative of 15x + 4, which is 15.

Now apply the product rule:

f'(x) = u'(x)v(x) + u(x)v'(x) = 5(5x + 23)^4(5)(15x + 4) + (5x + 23)^5(15).

So, the derivative formula for the given function is:

f'(x) = 5(5x + 23)^4(5)(15x + 4) + (5x + 23)^5(15)

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The IQR is calculated as the difference between the 75th and 25th percentiles of a dataset. It is not found by subtracting the mean from the maximum value of the dataset.

Data is the collection of data term that is organized and formatted in a specific way it typically contains fact observations or statistics that are collected through a process of measurement or research data set can be used to answer the question and help make an informed decision they can be used in a variety of ways such as to identify trends on cover patterns and make a prediction.

The interquartile range (IQR) is a statistical measure used to describe the spread or dispersion of a dataset. It is calculated as the difference between the 75th percentile (Q3) and the 25th percentile (Q1) of the dataset. In other words, the IQR represents the range of the middle 50% of the data.

To calculate the IQR, you first need to determine the median of the dataset. The median is the middle value of the dataset when it is arranged in order from smallest to largest. Then, you divide the dataset into two halves based on this median value: the lower half (values smaller than the median) and the upper half (values larger than the median).

Next, you determine the median of each of these halves separately. The median of the lower half is the first quartile (Q1), and the median of the upper half is the third quartile (Q3).

Finally, the IQR is calculated as the difference between Q3 and Q1 (IQR = Q3 - Q1).

So, to sum up, the IQR is not found by subtracting the mean from the maximum value of a dataset, but instead by calculating the difference between the 75th and 25th percentiles of the dataset.

Therefore, The IQR is calculated as the difference between the 75th and 25th percentiles of a dataset. It is not found by subtracting the mean from the maximum value of the dataset.

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dQ/dt is positive, the production is currently increasing at a rate of approximately 4.78 units per day.

To solve the problem, we need to use the multivariable chain rule of differentiation to find the rate of change of Q with respect to time t.

We have:

[tex]Q = 120K^{1/2}L^{1/3}[/tex]

Taking the derivative with respect to time t using the chain rule, we get:

dQ/dt = (dQ/dK)(dK/dt) + (dQ/dL)(dL/dt)

where dQ/dK and dQ/dL are the partial derivatives of Q with respect to K and L, respectively.

Using the chain rule, we can compute these derivatives as follows:

[tex]dQ/dK = 60K^{-1/2}L^{1/3}[/tex]

[tex]dQ/dL = 40K^{1/2}L^{-2/3}[/tex]

Next, we need to find the values of K, L, dK/dt, and dL/dt at the current time.

We are given:

K = 400 + 9t

L = 1000 - 4t

dK/dt = 9

dL/dt = -4

Substituting these values and simplifying, we get:

[tex]dQ/dt = (60/\sqrt{K} )L^{1/3}(dK/dt) + (40/3)(K^{1/2}/L^{2/3})(dL/dt)[/tex]

[tex]dQ/dt = (60/\sqrt{ (400+9t))(1000) } ^{1/3}(9) + (40/3)((400+9t)^{1/2} /(1000-4t)^{2/3})(-4)[/tex]

[tex]dQ/dt = 225(400+9t)^{-1/6} - 80(400+9t)^{1/2}(1000-4t)^{-2/3}[/tex]

Now we can find the value of dQ/dt at the current time t = 0:

[tex]dQ/dt = 225(400)^{−1/6} - 80(400)^{1/2}(1000)^{−2/3}[/tex]

dQ/dt ≈ 4.78.

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The sum of the infinite geometric series is 10.8.

First, we need to identify the common ratio (r) between the terms. To do this, divide the second term by the first term, the third term by the second term, and so on:

r = (-12/18) = -2/3

Now, we'll check if the common ratio is the same for other terms:

(8/-12) = -2/3 and (-16/3)/8 = -2/3

Since the common ratio is consistent, we can use the formula for the sum of an infinite geometric series:

S = a / (1 - r)

where S is the sum, a is the first term (18), and r is the common ratio (-2/3).

S = 18 / (1 - (-2/3))
S = 18 / (1 + 2/3)
S = 18 / (5/3)
S = (18 × 3) / 5
S = 54 / 5
S = 10.8

So, the sum of the infinite geometric series is 10.8.

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Answer:

1561.813ft32ft²

Step-by-step explanation:

To calculate the area of the wall which we will call the largest rectangle we must calculate the area of all rectangles on the wall and subtract their combined area from the total.

A = l*w

large rectangle 52.5ft * 33ft = 1732.5 ft²

rectangle A 6.25ft * 5.75ft = 35.9375ft²

rectangle B 3.125ft * 4ft = 12.5ft²

square C (9.5ft)² = 90.25ft²

rectangle D 4ft * 8ft = 32ft²

the total area of the wall needed to be painted

1732.5 ft² - 35.9375ft² - 12.5ft² - 90.25ft² - 32ft² = 1561.813ft32ft²

The critical point is x=4 and y=-1;

To find the critical points of f(x, y) = x² + xy + 2y² - 7x, you need to find the partial derivatives with respect to x and y and set them equal to 0.

Partial derivative with respect to x: fx(x, y) = 2x + y - 7
Partial derivative with respect to y: fy(x, y) = x + 4y

Setting both equal to 0:

2x + y - 7 = 0
x + 4y = 0

Solving this system of equations, we get x = 4 and y = -1. So, the critical point is (4, -1).

In summary, the critical point of f(x, y) = x² + xy + 2y² - 7x is (4, -1) with x = 4 and y = -1. To find this, calculate partial derivatives with respect to x and y, set them equal to 0, and solve the system of equations.

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Without the individual probability of a passenger showing up, we cannot calculate the exact probability of the number of people who show up exceeding the capacity of the plane

To solve this problem, we need to determine the probability that more than 65 people (the capacity of the plane) will show up from the 70 booked passengers.

Step 1: Identify the relevant information
- Maximum capacity of the plane: 65
- Number of people booked: 70

Step 2: Calculate the probability of each possible outcome
To exceed the capacity, at least 66 passengers must show up. We need to calculate the probability of 66, 67, 68, 69, and 70 passengers showing up. However, we don't have information on the individual probability of a passenger showing up. If we had this information, we could use the binomial probability formula.

Step 3: Express the final answer
Unfortunately, without the individual probability of a passenger showing up, we cannot calculate the exact probability of the number of people who show up exceeding the capacity of the plane. Please provide the probability of a passenger showing up so we can give you an accurate answer.

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We can be 95% confident that the true mean gas mileage for cars in the large community is at least 24.764 mpg.

To estimate the lower bound of the true mean gas mileage with a 95% confidence level, we can use the one-sample t-test with the formula

Lower bound = x - (tα/2 * (s/√n))

Where

x = sample mean = 25.25

tα/2 = t-value for the 95% confidence level with (n-1) degrees of freedom = 1.998 (from t-table or calculator)

s = population standard deviation = 4.99

n = sample size = 65

Substituting the values, we get

Lower bound = 25.25 - (1.998 * (4.99/√65)) ≈ 24.764

Therefore, we can estimate with 95% confidence that the true mean gas mileage is at least 24.764 mpg.

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--The given question is incomplete, the complete question is given

" Since 1975 the average fuel efficiency of U.S. cars and light trucks (SUVs) has increased from 13.5 to 25.8 mpg, an increase of over 90%. A random sample of 65 cars from a large community got a mean mileage of 25.25 mpg per vehicle. The population standard deviation is 4.99 mpg. Estimate the lower bound true mean gas mileage with 95% confidence.

Round your answer to 3 decimal places."--

The MVT guarantees the existence of at least one point c in (0, π) where

f'(c) = -2 sin 2c, which is equal to -2 sin 1.00229.

To apply the Mean Value Theorem (MVT) to the function f(x) = cos 2x on

the interval [0, π], we need to verify the two conditions:

f(x) is continuous on [0, π]

f(x) is differentiable on (0, π)

To check the continuity of f(x) on [0, π], we need to verify that the

function does not have any breaks or jumps on this interval. The cosine

function is continuous everywhere, so f(x) = cos 2x is also continuous on

[0, π].

To check the differentiability of f(x) on (0, π), we need to take the

derivative of f(x) and verify that it exists and is finite on this interval.

The derivative of f(x) = cos 2x is f'(x) = -2 sin 2x. This function is also

continuous everywhere, so it is differentiable on (0, π).

Since both conditions are satisfied, we can apply the MVT to f(x) on the

interval [0, π]. The theorem guarantees the existence of at least one

point c in (0, π) such that:

f'(c) = [f(π) - f(0)] / (π - 0)

Substituting the values for f(x) and f'(x), we get:

-2 sin 2c = [cos 2π - cos 2(0)] / π

-2 sin 2c = (-1 - 1) / π

sin 2c = 1 / π

Since the sine function is positive on (0, π), we know that 0 < 2c < π/2. Therefore, the only solution to sin 2c = 1 / π on this interval is:

2c ≈ 1.00229

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confidence interval: This tells us the degree of certainty or uncertainty that is existent in a sampling method.

To construct a 95% confidence interval for the population mean cholesterol level, we can use the following formula:

CI = x ± t*(s/√n)

where x is the sample mean, s is the sample standard deviation, n is the sample size, and t is the t-value from the t-distribution with n-1 degrees of freedom and a confidence level of 95%.

Substituting the given values, we have:

CI = 224 ± t*(12/√21)

Using a t-table with 20 degrees of freedom (since n-1=20), we find that the t-value for a 95% confidence interval is approximately 2.086.

Thus, the confidence interval is:

CI = 224 ± 2.086*(12/√21)

CI = (219.60, 228.40)

Therefore, the answer is option (c) (219.60, 228.40).

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