Use the traditional method to test the given hypothesis. Assume that the population is normally distributed and that the sample has been randomly selected. Select the appropriate response. With separate lines at the checkouts, a store manager finds that the standard deviation for the waiting times on Monday mornings is 5.7 minutes. After switching to a single waiting line, he finds that for a random sample of 29 customers the waiting times have a standard deviation of 4.9 minutes. Use a 0.025 significance level to test the claim that with a single line, waiting times vary less than with separate lines. Select the correct test statistic and critical value.

Test statistic: x^2 = 18.462. Critical value: x^2 = 15.308

Test statistic: x^2 = 20.692. Critical value: x^2 = 15.308

Test statistic: x^2 = 20.692. Critical value: x^2 = 7.815, 15.308

Test statistic: x^2 = 18.462. Critical value: x^2 = 7.815, 15.308

Answer:

1228

Step-by-step explanation:

To find the total square footage of carpet needed for the house, we first need to calculate the total square footage of the areas where we do not need carpet and then subtract that from the total square footage of the house.

The kitchen is 8 ft by 10 ft, so its area is:

8 ft x 10 ft =80 square feetThe dining room is 12 ft by 14, ft so its area is:

12 ft x 14 ft = 168 square feetThe bathroom is 4 ft by 6 ft, so its area is:

4 ft x 6 ft = 24 square feetTherefore, the total square footage of the areas where we do not need carpet is:

80 + 168 + 24 = 272 square feetTo find the total square footage of carpet needed for the house, we can subtract this from the total square footage of the house:

1500 - 272 = 1228 square feetTherefore, we need 1228 square feet of carpet for the house.

To calculate the amount of carpet needed, subtract the square footage of the rooms where you don't want new carpet (kitchen, dining room, bathroom) from the total house size. This results in 1228 square feet of carpet required.

First, let's determine the total square footage of the spaces where you don't want new carpet. The kitchen is 8 ft by 10 ft, which equals 80 square feet. The dining room is 12ft by 14ft, giving us 168 square feet. The bathroom is 4ft by 6 ft, equal to 24 square feet. When you add these together, that is a total of 272 square feet that should not be carpeted.

Since your total house size is 1500 square feet, we subtract the square footage of the kitchen, dining room, and bathroom from this total. So, 1500 square feet - 272 square feet equals 1228 square feet. Therefore, you need 1228 square feet of carpet for the house.

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In order to achieve $4,000 in three years at 4.5% simple interest, the principal must be equal to $29,629.63.

In Mathematics, simple interest can be calculated by using this formula:

S.I = PRT or S.I = A - P

Where:

By substituting the given parameters into the simple interest formula, we have;

4,000 = P × 4.5/100 × 3

4,000 = P × 0.045 × 3

4,000 = 0.135P

Principal, P = 4,000/0.135.

Principal, P = $29,629.63

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the inverse of the function f(x) = 3 + 5x is f^(-1)(x) = (x - 3) / 5.To find the inverse of the function f(x) = 3 + 5x, we need to solve for x in terms of y, then replace y with the inverse notation f⁻¹(x).

what is  inverse of the function  ?

The inverse of a function is a new function that "undoes" the effect of the original function, meaning that if we apply the inverse function to the output of the original function, we get back the input.

In the given question,

To find the inverse of the function f(x) = 3 + 5x, we need to solve for x in terms of y, then replace y with the inverse notation f⁻¹(x). The steps to find the inverse are as follows:

Step 1: Replace f(x) with y.

y = 3 + 5x

Step 2: Solve for x in terms of y.

y - 3 = 5x

x = (y - 3) / 5

Step 3: Replace x with f⁻¹(x) to get the inverse function.

f⁻¹(x) = (x - 3) / 5

Therefore, the inverse of the function f(x) = 3 + 5x is f⁻¹(x) = (x - 3) / 5.

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Answer:

To find the percentage, you need to divide the first number by the second number and then multiply by 100. In this case:

32 ÷ 50 = 0.64

Multiplying by 100 gives:

0.64 × 100 = 64

Therefore, 32 is 64% of 50.

Step-by-step explanation:

Answer:

64%

Step-by-step explanation:

32/50 x 2 (you need to make it over 100)

= 64/100

= 64%

The total miles drive by Suzy in 18 hours when she can drive 53 miles in 1 hour is equal to 954 miles.

If Suzy can drive 53 miles in 1 hour,

Using the formula of speed based on distance and time we have,

Speed = Distance / Time

Substitute the values in the formula we get,

⇒ Speed = 53 miles / 1 hour

⇒ Speed  = 53 miles/hour

Use this information to find out how far Suzy can drive in 18 hours we get,

Now, Speed =  53 miles/hour

Time = 18 hours

Distance = Speed x Time

Substitute the value of speed and time we get,

⇒ Distance  = 53 miles/hour x 18 hours

⇒ Distance = 954 miles

Therefore, Suzy can drive 954 miles in 18 hours.

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The equivalenet expression is 54[tex]n^{-11}[/tex]

Any mathematical statement that includes numbers, variables, and an arithmetic operation between them is known as an expression or algebraic expression.

The way of representing huge numbers in terms of powers is known as an exponent. Exponent, then, is the number of times a number has been multiplied by itself.

To simplify the given expression, we need to apply the power of a power rule, which states that to raise a power to another power, we need to multiply the exponents.

Starting with:

([tex]6n^-5[/tex])([tex]3n^-3[/tex])²

We can simplify as follows:

([tex]6n^-5[/tex])([tex]9n^-6[/tex])

Now, we can use the product of powers rule, which states that when multiplying two powers with the same base, we add their exponents.

Therefore:

6 x 9 = 54

[tex]n^-5 * n^-6 = n^-11[/tex]

So the simplified expression is:

[tex]54n^-11[/tex]

Therefore, the expression [tex](6n^-5)(3n^-3)^2[/tex] is equivalent to [tex]54n^-11.[/tex]

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The expression that is equal to (6n-5)(3n-3) option D, 54n11.

Mathematical expressions consist of at least two numbers or variables, at least one arithmetic operation, and a statement.

We can use the distributive property of multiplication to expand the expression (6n - 5)(3n - 3) as follows:

(6n - 5)(3n - 3) = 6n(3n) - 6n(3) - 5(3n) + 5(3)

                 = 18n² - 18n - 15n + 15

                 = 18n² - 33n + 15

Therefore, the expression that is equivalent to (6n - 5)(3n - 3) is 18n² - 33n + 15, which is option D.

So, the answer is option D, 54n11.

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Therefore, Janelle would need 1872 square inches of plywood to make the chest.

A square inch (sometimes known as an in2 or sq. in.) is a unit of area measurement. A square with sides that are one inch long has an area of one square inch: Two lengths are used to measure a square area.

The areas of all the sides must be added up in order to determine the surface area of the chest. For instance, if we use 1/2 inch plywood and the chest is 24 inches by 12 inches by 18 inches, the surface area of the chest would be:

Top and bottom: 2 * (24 inches * 12 inches) = 576 square inches

Front and back: 2 * (18 inches * 12 inches) = 432 square inches

Sides: 2 * (24 inches * 18 inches) = 864 square inches

Total surface area = 576 + 432 + 864 = 1872 square inches

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Answer: C

Step-by-step explanation: C



The standard deviation of the sampling distribution is approximately 0.3292.

The behaviour of the sampling distribution of the mean is described by the central limit theorem, a key conclusion in statistics. It asserts that regardless of how the population distribution is shaped, if a random sample of size n is taken from a population with mean and standard deviation, the distribution of sample means will tend towards a normal distribution as n increases.

Because it enables us to utilise the normal distribution to draw conclusions about the population mean based on sample means, the central limit theorem has significant practical ramifications. Additionally, it offers a foundation for confidence interval estimation and statistical hypothesis testing.

The standard deviation is given by the formula:

SD = σ/√(n)

Now, substituting the value of σ = 40, n = 147,400 we have:

SD = σ/√(n) = 40/√(147400) ≈ 0.3292

Hence, the standard deviation of the sampling distribution is approximately 0.3292.

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Answer: The primary rectangle contains a length of 2a units (since it is labeled as "2a" within the diagram), so its zone is 2a x a = 2a^2 square units.

The moment rectangle contains a length of 3a units (since it is labeled as "3a" within the diagram), so its range is 3a x a = 3a^2 square units.

The third rectangle contains a length of 4a units (since it is labeled as "4a" within the graph), so its range is 4a x a = 4a^2 square units.

To discover the overall region of the expansive rectangle, able to include the zones of these three rectangles:

Add up to zone = 2a^2 + 3a^2 + 4a^2

Disentangling this expression, we are able combine the like terms (2a^2, 3a^2, and 4a^2) to urge:

Add up to range = (2 + 3 + 4) a^2

Step-by-step explanation:

Using the given angle of depression the equation (D) cos(24) = x/45 will be used to find the answer.

The angle of depression is the angle formed by the horizontal line and the horizontal line's observation of the item.

When we know the angles and the distance of an object from the ground, it is primarily utilized to find the distance between the two objects.

The angle from the horizontal downward to an item is referred to as the "angle of depression."

The line of sight of an observer would be below the horizontal.

So, in the given situation:
We will find the base which is the distance of the boat from the land.

Which means:
hypotenuse/Base

Which is represented by Cosx.

The angle is 24°.

Then, the equation for a solution would be:

cos(24) = x/45

Therefore, using the given angle of depression the equation (D) cos(24) = x/45 will be used to find the answer.

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The value of x is given as follows:

x = 4.2 cm.

The value of x is obtained applying the proportions in the context of the problem.

The ratio between the volumes is given as follows:

3375/512 = 6.59

The side lengths are measured in units, while the volume is measured in cubic units, hence the proportion to obtain the value of x is given as follows:

8/x = cubic root of 6.59

8/x = 1.9

x = 8/1.9

x = 4.2 cm.

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Based on the word problem, the answer is not one of the given options (E. NOTA).

In this case, we have 9 letters and we want to select all of them, so n = 9 and r = 9. Therefore:

A = 9!

A = 362,880

B) The hypotenuse of a right triangle can be found using the Pythagorean theorem:

c^2 = a^2 + b^2

In this case, we have a = 9 and b = 12. Therefore:

c^2 = 9^2 + 12^2

c = 15

So, B = 15.

y - 9 = 3(x - 6)

y - 9 = 3x - 18

y = 3x - 9

The y-intercept of this line is -9, so C = -9.

Therefore, A + B + C = 362,880 + 15 - 9 = 362,886.

So the answer is not one of the given options (E. NOTA).

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Answer:

Center= -4,8

Radius=7

Step-by-step explanation:

Answer:

350° 33' 10".

Step-by-step explanation:

To convert the decimal degree 350.5527° to degrees, minutes, and seconds, we can use the following steps:

Therefore, 350.5527° is equivalent to 350° 33' 10".

the total number of boxes with at least 20 but fewer than 60 broken crayons is  33.To answer this question, we need to use the stem-and-leaf plot to count the number of boxes with at least 20

what is at least ?

"At least" is a phrase that is used to indicate a minimum quantity or degree of something. It means that the stated quantity or degree is the smallest amount that is acceptable or possible. For example, if someone says "I need at least 10 dollars,"

In the given question,

To answer this question, we need to use the stem-and-leaf plot to count the number of boxes with at least 20 but fewer than 60 broken crayons.

From the stem-and-leaf plot, we can see that the stems 2, 3, 4, and 5 have leaves that add up to at least 20 but fewer than 60:

Stem 2 has leaves 3 and 8, which add up to 11.

Stem 3 has leaf 3, which adds up to 3.

Stem 4 has leaves 0 and 9, which add up to 9.

Stem 5 has leaves 1 and 9, which add up to 10.

Therefore, the total number of boxes with at least 20 but fewer than 60 broken crayons is 11 + 3 + 9 + 10 = 33.

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The graph that shows the solution to the system of linear inequalities is the Graph D.

Here, we are given first inequality as:

Y > -1/3x + 2

The graph of this inequality is a dotted straight line( since the inequality is strict) that passes through (6,0) and (0,2) with shaded region away from the origin ( since it fails zero test)

Second inequality is given by:

y > 2x - 3

The graph of this inequality is a dotted straight line( since the inequality is strict) that passes through (3/2,0) and (0,-3) with shaded region away towards the origin ( since it passes zero test). On plotting it's graph, we get the solution.

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The field's length is therefore three times its breadth, or 3(50), or 150 yards, and its width is 50 yards.

A this double shape's perimeter is the space encircling its outside edge. It is the length of the object's sides. As an illustration, the perimeter of a rectangle is equivalent to the total of its four sides' lengths.

given

Assume that the rectangular field has a width of "x" yards.

The problem states that the field's length is three times its breadth, or three times yards.

The lengths of all the sides make up the rectangle's perimeter, therefore we can write:

[tex]Perimeter = 2 (length + width).[/tex]

In place of the values we hold:

[tex]400 = 2(3x + x)\\400 = 2(4x) (4x)\\400 = 8x\\x = 50[/tex]

The field's length is therefore three times its breadth, or 3(50), or 150 yards, and its width is 50 yards.

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Answer:

11 dimes and nickels.

Step-by-step explanation:

22 total coins divided by 2 equals 11 for each.

the number 2 represents the dimes and nickels, 22 for the total amount of coins, and 11 for the answer.

Answer:15 nickels  and  7 dimes.

Step-by-step explanation:

The equation of the reflected graph is y = -3ˣ.

To reflect a graph over the x-axis, we need to negate the y-coordinates of all the points on the original graph. In other words, if a point (x, y) is on the original graph, its reflection over the x-axis would be (x, -y).

Let's apply this concept to the exponential function f(x) = 3ˣ. The graph of this function is an upward sloping curve that passes through the point (0,1) on the y-axis. If we reflect this graph over the x-axis, the point (0,1) will be mapped to (0,-1), as the x-coordinate remains the same, but the y-coordinate changes sign.

To find the equation of the reflected graph, we need to replace y with -y in the equation of the original function f(x) = 3ˣ. This gives us:

-y = 3ˣ

To isolate y, we can multiply both sides by -1:

y = -3ˣ

This function is a downward sloping curve that passes through the point (0,-1) on the x-axis.

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Answer:72

Step-by-step explanation:you would add the 9 to the other side and then it would give you the answer of x=72. You do this because it is -9 if it were say x+9 then you would subtract 9 from both sides

y is a function of x.

A mathematical relationship between an input (x) and an output (y) where each input has exactly one output is known as a function. There are no multiple possibilities of y for a single value of x in the preceding equation, which expresses y as a combination of x², x, and a constant term. As a result, the equation meets the criteria for a function.

Yes, y = 2x² - 4x + 10 is a function.

A function is a mathematical rule that assigns to each input (x-value) exactly one output (y-value). In the given equation, for any value of x, we can calculate the corresponding value of y using the given equation. Therefore, y is a function of x.

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Hence, 7, 22, 37, and 52 are the first four terms in the arithmetic series with initial term 7 and common difference 15.

Algebraic progression is a series of numbers where each term following the first is derived by multiplying the previous president by a constant known as the common difference (d). An arithmetic progression often takes the form: A, A+D, A+2D, A+3D,... where "a" stands for the initial keyword and "d" for the common distinction.

given

The sequence's initial term is 7, and the shared discrepancy is 15. We can continuously add 15 to the preceding word to find the next terms.

As a result, the arithmetic sequence's first four terms are:

Initial term = 7

Term two: 7 plus 15 equals 22

Third term = 22 plus 15 equals 37

Fourth term: 37 plus 15 equals 52

Hence, 7, 22, 37, and 52 are the first four terms in the arithmetic series with initial term 7 and common difference 15.

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Answer:

the triangle arereflected across the line y=x

a.The probability distribution table for the first six attempts is shown below:

X P(X=k)

1 0.44

2 0.56 ×0.44

3 0.56²×0.44

4 0.56³ × 0.44

5 0.56⁴ ×0.44

6 0.56⁵×0.44

b.  the probability is 0.1399.

c. the quarterback can expect to throw about 2.27 passes before completing one.

d. the probability is 0.1865.

e. the probability is 0.7349.

The possibility or chance of an event occurring is measured by probability. The expression is given as a number between 0 and 1, with 0 denoting impossibility and 1 denoting certainty. Compared to occurrences with a probability closer to 0, those with a probability closer to 1 are more likely to occur.

a. To construct a probability distribution table for the number of passes attempted before the quarterback has a completion, we can use the geometric probability distribution, which is given by:

P(X=k) = [tex](1-p)^{k-1}[/tex]×p

where X is the number of attempts before the completion, p is the probability of completion on each attempt, and k is the number of attempts.

The probability distribution table for the first six attempts is shown below:

X P(X=k)

1 0.44

2 0.56 ×0.44

3 0.56²×0.44

4 0.56³ × 0.44

5 0.56⁴ ×0.44

6 0.56⁵×0.44

b. The probability that the quarterback throws 3 incomplete passes before he has a completion is given by:

P(X=3) = (1-0.44)³⁻¹× 0.44 × (1-0.44)⁰

= 0.56²×0.44

= 0.1399

Therefore, the probability is 0.1399.

c. The expected number of passes that the quarterback can throw before he completes a pass is given by the formula:

E(X) = 1/p

where p is the probability of completion on each attempt.

In this case, p = 0.44, so the expected number of passes is:

E(X) = 1/0.44

= 2.27

Therefore, the quarterback can expect to throw about 2.27 passes before completing one.

d. The probability that it takes more than 5 attempts before the quarterback completes a pass is given by:

P(X > 5) = 1 - P(X <= 5)

= 1 - [P(X=1) + P(X=2) + P(X=3) + P(X=4) + P(X=5)]

= 1 - [0.44 + (0.56 × 0.44) + (0.56² ×0.44) + (0.56³ × 0.44) + (0.56⁴×0.44)]

= 0.1865

Therefore, the probability is 0.1865.

e. If the quarterback throws 8 passes on the opening drive, the probability that he completes at least half of them is given by the binomial probability distribution, which is given by:

P(X ≥ 4) = 1 - P(X < 4)

where X is the number of completed passes and the probability of completion on each attempt is p = 0.44.

Using the binomial probability distribution table or calculator, we can find:

P(X≥4) = 1 - [P(X=0) + P(X=1) + P(X=2) + P(X=3)]

= 1 - [0.56⁸ + (8× 0.56⁷×0.44) + (28 × 0.56⁶ × 0.44²) + (56× 0.56⁵×0.44³)]

= 0.7349

Therefore, the probability is 0.7349.

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This means that the median weight of a female child at 31.48 months is 28 pounds (approximately) base on logarithmic function.

Q1.1: The equation for the amount of money in the account after t years, compounded annually, can be given by:

A = P(1 + r/100)^t

where A is the amount of money in the account after t years, P is the principal amount invested, r is the annual interest rate, and t is the number of years.

Plugging in the values given in the problem, we get:

A = 1200(1 + 4.25/100)^t

Q1.2: We need to solve for t in the equation:

3000 = 1200(1 + 4.25/100)^t

Dividing both sides by 1200, we get:

2.5 = (1 + 4.25/100)^t

Taking the natural logarithm of both sides, we get:

ln 2.5 = t ln (1 + 4.25/100)

Solving for t, we get:

t = ln 2.5 / ln (1 + 4.25/100) ≈ 15.91 years

So, it will take approximately 15.91 years for the amount of money in the account to reach $3000.

Q2.1: To graph the function W = 7.5 + 5.9 ln(M + 1), we can use a graphing calculator or software. Here is a possible graph:

Graph of W = 7.5 + 5.9 ln(M + 1)

Q2.2: To find W ^−1(28), we need to solve the equation:

28 = 7.5 + 5.9 ln(M + 1)

Subtracting 7.5 from both sides, we get:

20.5 = 5.9 ln(M + 1)

Dividing both sides by 5.9, we get:

ln(M + 1) ≈ 3.474576

Taking the inverse logarithm of both sides, we get:

M + 1 ≈ e^3.474576

M ≈ e^3.474576 - 1 ≈ 31.48 months

So, W ^−1(28) ≈ 31.48 months. This means that the median weight of a female child at 31.48 months is 28 pounds (approximately).

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===================================================

Explanation:

We have 5 green in the 1st row and 4 green in the 2nd row.

The LCM is 5*4 = 20.

The ratio [tex]6 \text{ yellow} = 5 \text{ green}[/tex] scales up to [tex]24 \text{ yellow} = 20 \text{ green}[/tex] after multiplying both sides by 4.

The ratio [tex]4 \text{ green} = 3 \text{ purple}[/tex] scales up to [tex]20 \text{ green} = 15 \text{ purple}[/tex] after multiplying both sides by 5.

--------------

These set of ratios

[tex]6 \text{ yellow} = 5 \text{ green}\\\\4 \text{ green} = 3 \text{ purple}\\\\[/tex]

scale up to

[tex]24 \text{ yellow} = 20 \text{ green}\\\\20 \text{ green} = 15 \text{ purple}\\\\[/tex]

The key is the "20 green" on each line. This leads to the ratios linking up.

If A = B and B = C, then A = C (transitive property).

So we can say [tex]24 \text{ yellow} = 20 \text{ green} = 15 \text{ purple}\\\\[/tex]

That simplifies to [tex]24 \text{ yellow} = 15 \text{ purple}\\\\[/tex]

We can divide both sides by 3 to get [tex]8 \text{ yellow} = 5 \text{ purple}\\\\[/tex]

--------------

We now have these set of ratios

[tex]8 \text{ yellow} = 5 \text{ purple}\\\\5 \text{ purple} = 2 \text{ red}\\\\[/tex]

Connect those two equations together to get

[tex]8 \text{ yellow} = 2 \text{ red}\\\\[/tex]

Lastly, divide both sides by 4

[tex]4 \text{ yellow} = 1 \text{ red}\\\\[/tex]

The area the grass seed needs to cover is 7,425 square meters.

To find the total area of the lawn excluding the pool, we first need to calculate the area of the pool. Using the formula for the area of a rectangle, we multiply the length and width of the pool together to get:

= 7.5 m x 3.25 m

= 24.375 square meters

Next, we can find the total area of the lawn by subtracting the area of the pool from the total area of the rectangle formed by the lawn:

= 50 m x 150 m

= 7,500 square meters

So, the area the grass seed needs to cover is:

= 7,500 square meters - 24.375 square meters

= 7,425 square meters.

Full question" Marcos wants to buy grass seed to cover his whole lawn, except for the pool. The pool is 7 1/2 m by 3 1/4 m. Find the area the grass seed needs to cover. The dimensions of the lawn are 50 m x 150 m.

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Here, we want to get the final volume

From the general gas equation, we have it that:

[tex]\dfrac{P_1V_1}{T_1} =\dfrac{P_2V_2}{T_2}[/tex]

From the question, we have it that:

P1 is the initial pressure which is 475 torr

V1 is the initial volume which is 296 mL

T1 is the initial temperature which we have to convert to absolute value by adding 273.15 K ([tex]68 + 273.15 = 341.15 \ \text{K}[/tex])

P2 is the final pressure that is the same as the initial which is 475 torr

V2 is the final volume that we want to calculate

T2 is the final temperature which is 273.15 K (0 degrees Celsius is 273.15 K)

Substituting the values, we have:

            [tex]\dfrac{475\times296}{341.15}=\dfrac{475\times V_2}{273.15}[/tex]

[tex]V_2=\cfrac{475\times296\times273.15}{341.15\times475} =\boxed{\bold{237 \ mL}}[/tex]

We could have solved this by using Charles' law that relates temperature to volume (volume is directly proportional to temperature)