Pls help (part 4)
Give step by step explanation!

The 98% confidence interval for the true mean of exam 2 is approximately (62.81, 81.75).

To construct a 98% confidence interval for the true mean of exam 2, we will use the provided information:

Mean (μ) = 72.28
Standard deviation (σ) = 18.375
Sample size (n) = 25

First, we need to find the standard error of the mean (SE):
SE = σ / √n = 18.375 / √25 = 18.375 / 5 = 3.675

Next, we need to find the critical value (z) for a 98% confidence interval. The critical value for a 98% confidence interval is 2.576 (from the z-table).

Now we can calculate the margin of error (ME):
ME = z × SE = 2.576 × 3.675 ≈ 9.47

Finally, we can calculate the confidence interval:
Lower limit = μ - ME = 72.28 - 9.47 ≈ 62.81
Upper limit = μ + ME = 72.28 + 9.47 ≈ 81.75

So, the 98% confidence interval for the true mean of exam 2 is approximately (62.81, 81.75).

To learn more about confidence interval here;

brainly.com/question/24131141#

#SPJ11

Answer:

93.7 meters

Step-by-step explanation:

We can use similar triangles to solve this problem. Similar triangles are triangles that have the same shape but possibly different sizes. They have proportional sides.

Let's denote the height of the tower as 'h'. According to the given information, the height of the pole is 2.7m and it casts a shadow that is 1.27m long. Similarly, the tower casts a shadow that is 44.5m long.

We can set up a proportion using the heights and shadows of the pole and the tower:

height of pole / length of shadow of pole = height of tower / length of shadow of tower

Plugging in the values we have:

2.7 / 1.27 = h / 44.5

Now we can cross-multiply and solve for 'h':

2.7 * 44.5 = 1.27 * h

119.15 = 1.27h

Dividing both sides by 1.27:

h = 119.15 / 1.27

h ≈ 93.7

So, the height of the tower is approximately 93.7 meters, rounded to the nearest meter.

18, 21, 24, 27, 30 can be gotten when 6, 7, 8, 9, 10 are multiplied three times.

Sequence is  an ordered list of numbers that often follow a specific pattern or rule. Sequence is a list of things that are in order.

How to determine this

6, 7, 8, 9, 10 are related to 18, 21, 24, 27, 30

6 * 3 = 18

7 * 3 = 21

8 * 3 = 24

9 * 3 = 27

10 * 3 = 30

All of them followed the same sequence of being multiplied by 3.

6, 7, 8, 9, 10 when multiplied thrice will give 18, 21, 24, 27, 30.

Read more about Sequence

https://brainly.com/question/15458247

#SPJ1

Position vector r(t) is given by

[tex]r(t) = (1/3)t^3 i + e^t j + e^{5t} k.[/tex]

Here's the step-by-step explanation:

1. Integrate each component of r'(t) with respect to t:
  ∫[tex](t^2) dt = (1/3)t^3 + C1[/tex] (for i-component)
  ∫[tex](e^t) dt = e^t + C2[/tex] (for j-component)
  ∫[tex](5te^{5t}) dt = e^{5t} + C3[/tex] (for k-component)

2. Apply the initial condition r(0) = i + j + k:
  r(0) = (1/3)(0)³ + C1 i + e⁰ + C2 j + e⁵ˣ⁰ + C3 k = i + j + k
  This implies that C1 = 1, C2 = 0, and C3 = 0.

3. Plug in the values of C1, C2, and C3 to find r(t):
  [tex]r(t) = (1/3)t^3 + 1 i + e^t j + e^{5t} k[/tex]

So, the position vector r(t) is given by [tex]r(t) = (1/3)t^3 i + e^t j + e^{5t} k.[/tex]

Learn more about Position vector.

brainly.com/question/14552074

#SPJ11

Answer:

a. The total loss from buying and selling 300 shares at these prices can be calculated as follows:

Total cost of buying the stock = 300 shares x $41/share = $12,300

Total proceeds from selling the stock = 300 shares x $24.98/share = $7,494

Loss = Total cost - Total proceeds = $12,300 - $7,494 = $4,806

Therefore, the loss from buying and selling 300 shares of General Motors stock at these prices is $4,806.

b. To express the loss as a percent of the purchase price, we can use the following formula:

Loss percentage = (Loss / Total cost) x 100%

Substituting the values we found, we get:

Loss percentage = ($4,806 / $12,300) x 100% = 39.2%

Rounded to the nearest tenth of a percent, the loss percentage is 39.2%.

Answer:

Domain: (−∞,∞),{x|x∈R}(-∞,∞),{x|x∈ℝ}Range: (−∞,∞),{y|y∈R}, There are no vertical or horizontal asymptotes and x is 6.11

Step-by-step explanation:

Unsure on what Im solving for but here’s a couple different possibilities

The sequence above is an arithmetic sequence.

The common difference is -4.

In Mathematics and Geometry, the nth term of an arithmetic sequence can be calculated by using this expression:

aₙ =  a₁ + (n - 1)d

Where:

Next, we would determine the common difference as follows.

Common difference, d = a₂ - a₁

Common difference, d = 13 - 17 = 9 - 13

Common difference, d = -4.

Next, we would determine the common ratio as follows;

Common ratio, r = a₂/a₁

Common ratio, r = 13/17 ≠ 9/13

Common ratio, r = 0.7647 ≠ 0.6923

Read more on arithmetic sequence here: brainly.com/question/24989563

#SPJ1

The correct answer to the above threads-based question Option is d. 1/6 inch.

The phrase "12 threads per inch" refers to the number of ridges or threads on the screw shaft for every inch of its length. This indicates that the space between two consecutive threads for a single thread is 1/12 inch.

When the screw turns two complete revolutions, it travels a distance equal to the screw pitch. The spacing between neighboring threads is specified as the screw pitch. Because there is just one thread in this scenario, the pitch is 1/12 inch.

When the screw completes two complete rotations, it advances into the nut a distance equal to the screw pitch, which is 1/12 inch. Since the answer choices are given in fractions, we can simplify 1/12 to 1/6 by dividing both the numerator and denominator by 2. Hence, the correct answer is d) 1/6 inch.

To learn more about revolutions of thread, visit:

https://brainly.com/question/16533738

#SPJ11

The correct answer to the above threads-based question Option is d. 1/6 inch.

The phrase "12 threads per inch" refers to the number of ridges or threads on the screw shaft for every inch of its length. This indicates that the space between two consecutive threads for a single thread is 1/12 inch.

When the screw turns two complete revolutions, it travels a distance equal to the screw pitch. The spacing between neighboring threads is specified as the screw pitch. Because there is just one thread in this scenario, the pitch is 1/12 inch.

When the screw completes two complete rotations, it advances into the nut a distance equal to the screw pitch, which is 1/12 inch. Since the answer choices are given in fractions, we can simplify 1/12 to 1/6 by dividing both the numerator and denominator by 2. Hence, the correct answer is d) 1/6 inch.

To learn more about revolutions of thread, visit:

https://brainly.com/question/16533738

#SPJ11

a) For Jamal's class with 500 students and a z-score of -1, approximately 171 actual students scored higher than Jamal on the quiz.

b) For a distribution with a mean of 50 and a standard deviation of 5, the raw score corresponding to a z-score of +2.6 is 62.

If Jamal's z-score is -1, it means that his score is one standard deviation below the mean. Since the mean is 50 and the standard deviation is 5, we can calculate the actual score corresponding to a z-score of -1 using the formula

z = (x - μ) / σ

where z is the z-score, x is the actual score, μ is the mean, and σ is the standard deviation.

Rearranging the formula to solve for x, we get

x = z × σ + μ

x = -1 × 5 + 50

x = 45

So Jamal's actual score is 45. To find out how many students scored higher than Jamal, we need to know the proportion of the class that scored higher than him. We can use a z-table to look up the proportion of the distribution above a z-score of -1.

The area between the mean and a z-score of -1 is 0.3413 (found on the z-table), which means that approximately 34.13% of the class scored higher than Jamal.

Therefore, the number of actual students who scored higher than Jamal is:

500 × 0.3413 = 170.65, which we can round to approximately 171.

To find the raw score for a z-score of +2.6, we can use the same formula

z = (x - μ) / σ

where z is +2.6, μ is 50, and σ is 5. Rearranging the formula to solve for x, we get

x = z × σ + μ

x = 2.6 × 5 + 50

x = 62

So the raw score for a z-score of +2.6 is 62.

Learn more about z-score here

brainly.com/question/15016913

#SPJ4

Step-by-step explanation:

Essentially Zero probability  ......   VERY unlikely that it will land on its edge.

The Partial F test is used to compare two nested linear regression models, where Model B is a more complex version of Model A. The null hypothesis of the test is that the additional variables in Model B do not have a significant impact on the dependent variable, while the alternative hypothesis is that they do.

To compute the Partial F test statistic, we need to first fit both models and obtain their respective residual sum of squares (RSS). Then, we can use the formula:

F = (RSS_A - RSS_B) / (p - q) * (RSS_B / (n - p))

where p is the number of variables in Model A (excluding the intercept), q is the number of additional variables in Model B (excluding those already in Model A), and n is the sample size.

The resulting F value follows an F-distribution with (q, n - p) degrees of freedom. We can then calculate the p-value by comparing this F value to the critical value of the F-distribution with the same degrees of freedom, using a significance level of 0.05.

If the p-value is less than 0.05, we reject the null hypothesis and conclude that Model B is a better fit than Model A. Otherwise, we fail to reject the null hypothesis and conclude that there is no significant difference between the two models.

To learn more about linear regression model : brainly.com/question/31328926

#SPJ11  

The 95%-confidence interval is:

Confidence Interval = [67.0 - 2.76, 67.0 + 2.76] ≈ [64.24, 69.76]

a) The estimate of the height can be found by taking the average of the measurements:

Height Estimate = (67+69+65+68+66)/5 = 67.0

Therefore, the estimated height of the building is 67 meters.

b) The 99%-confidence interval can be found using the formula:

Confidence Interval = [Height Estimate - Margin of Error, Height Estimate + Margin of Error]

where the Margin of Error is given by:

Margin of Error = Z * (Standard Deviation / sqrt(n))

Here, n = 5 (number of measurements), Z is the value from the standard normal distribution that corresponds to the 99% confidence level, and the standard deviation is given as 4.

Using a table or calculator, we find that Z = 2.576.

Plugging in the values, we get:

Margin of Error = 2.576 * (4 / sqrt(5)) ≈ 4.14

Therefore, the 99%-confidence interval is:

Confidence Interval = [67.0 - 4.14, 67.0 + 4.14] ≈ [62.86, 71.14]

c) To estimate the standard deviation, we can use the sample standard deviation formula:

Sample Standard Deviation = sqrt(1/(n-1) * Sum((Xi - Xbar)^2))

where Xbar is the sample mean, Xi are the individual measurements, and n is the sample size.

Plugging in the values, we get:

Xbar = (67+69+65+68+66)/5 = 67.0

Sample Standard Deviation = sqrt(1/(5-1) * ((67-67)^2 + (69-67)^2 + (65-67)^2 + (68-67)^2 + (66-67)^2)) ≈ 1.58

Therefore, the estimated standard deviation for the measurement error is 1.58.

d) To find the 95%-confidence interval when the standard deviation is unknown, we can use the t-distribution with n-1 degrees of freedom. The formula for the confidence interval is:

Confidence Interval = [Height Estimate - Margin of Error, Height Estimate + Margin of Error]

where the Margin of Error is given by:

Margin of Error = t * (Sample Standard Deviation / sqrt(n))

Here, n = 5 (number of measurements), t is the value from the t-distribution that corresponds to the 95% confidence level and 4 degrees of freedom (n-1), and the sample standard deviation is 1.58 (calculated in part c).

Using a table or calculator, we find that t = 2.776.

Plugging in the values, we get:

Margin of Error = 2.776 * (1.58 / sqrt(5)) ≈ 2.76

Therefore, the 95%-confidence interval is:

Confidence Interval = [67.0 - 2.76, 67.0 + 2.76] ≈ [64.24, 69.76]

To learn more about Standard Deviation  visit:

https://brainly.com/question/23907081

#SPJ11

S = {1 - 2x², 1 + 3x - x², 1 + 2x + x³} is linearly independent in P3(R).

To determine if the set S is linearly independent in P3(R), we can use the linear combination method. We set a linear combination of the vectors in S equal to the zero vector:

c1(1 - 2x²) + c2(1 + 3x - x²) + c3(1 + 2x + x³) = 0

Now, we equate the coefficients of like terms:

c1 + c2 + c3 = 0
3c2 + 2c3 = 0
-2c1 - c2 + c3 = 0

This system of linear equations has only the trivial solution, where c1 = c2 = c3 = 0, which implies that the set S is linearly independent in P3(R).

To know more about zero vector click on below link:

https://brainly.com/question/31129939#

#SPJ11

complete question:

Consider S = {1 − 2x^2, 1 + 3x − x^2, 1 + 2x + x3} ⊆ P3(R)  is S linearly independent in P3(R) ?

The zeros of the given cubic equation are x = 2, x = 0.75, and x = -5

The linear factors are (x - 2), (4x - 3), and (x + 5)

From the question, we are to determine the zeros of the given cubic equation

From the given information,

The cubic equation is

g(x) = 4x³ + 9x² - 49x + 30

First, we will test values to determine one of the roots of the equation

Test x = 0

g(0) = 4x³ + 9x² - 49x + 30

g(0) = 4(0)³ + 9(0)² - 49(0) + 30

g(0) = 30

Therefore, 0 is a not a root

Test x = 1

g(1) = 4x³ + 9x² - 49x + 30

g(1) = 4(1)³ + 9(1)² - 49(1) + 30

g(1) = 4 + 9 - 49 + 30

g(1) = -6

Therefore, 1 is a not a root

Test x = 2

g(1) = 4x³ + 9x² - 49x + 30

g(1) = 4(2)³ + 9(2)² - 49(2) + 30

g(1) = 32 + 36 - 98 + 30

g(1) = 0

Therefore, 2 is a root

Then,

(x - 2) is a factor of the cubic equation

(4x³ + 9x² - 49x + 30) / (x - 2) = (4x² + 17x - 15)

Now,

We will solve 4x² + 17x - 15 = 0 to determine the remaining roots

4x² + 17x - 15 = 0

4x² + 20x - 3x - 15 = 0

4x(x + 5) -3(x + 5) = 0

(4x - 3)(x + 5) = 0

Thus,

4x - 3 = 0 or x + 5 = 0

4x = 3 or x = -5

x = 3/4 or x = -5

x = 0.75 or x = -5

Hence,

The zeros are x = 2, x = 0.75, and x = -5

The linear factors are (x - 2), (4x - 3), and (x + 5)

Learn more on Solving Cubic equations here: brainly.com/question/13667615

#SPJ1

In the circle on the left bottom, 4

the circle on the right bottom, 5

the square on the right, -15

A singular point occurs when the coefficient of the highest derivative term, in this case y'', becomes zero. At x=1, the coefficient (x²-16)³(x-1) becomes 0, making x=1 a singular point for the given equation.

To determine if x=1 is a singular point for the equation (x²-16)³(x-1)y'' - 2xy' y = 0, we can examine the coefficients of the equation.

In more detail, a singular point in a differential equation is a point where the coefficients of the highest derivative terms are either undefined or equal to zero. For our equation, the highest derivative term is y'' and its coefficient is (x²-16)³(x-1). When x=1, this coefficient becomes (1²-16)³(1-1) = (1-16)³(0) = (-15)³(0) = 0.

Since the coefficient is equal to zero at x=1, it confirms that x=1 is indeed a singular point for the given equation.

To know more about derivative click on below link:

https://brainly.com/question/25324584#

#SPJ11

To express vector v as a linear combination of vectors v1, v2, and v3 and find Av, we need to know the components of vector v, and then we can set up and solve a system of linear equations to determine the coefficients c1, c2, and c3, and calculate Av using matrix multiplication.

In order to express vector v as a linear combination of vectors v1, v2, and v3, we need to know the components of vector v. The components of a vector represent its values along each coordinate axis or direction. Let's assume that the components of vector v are denoted as v_x, v_y, and v_z, representing its values along the x, y, and z axes respectively.

Given that, we can express vector v as a linear combination of vectors v1, v2, and v3 as follows:

v = c1 * v1 + c2 * v2 + c3 * v3

where c1, c2, and c3 are constants that represent the coefficients or weights of the respective vectors v1, v2, and v3 in the linear combination.

To find the coefficients c1, c2, and c3, we can set up a system of linear equations based on the components of vector v and the given vectors v1, v2, and v3. We can then solve this system of linear equations to determine the values of c1, c2, and c3.

Once we have the coefficients c1, c2, and c3, we can also calculate Av, which represents the vector resulting from the matrix multiplication of a matrix A (formed by stacking v1, v2, and v3 as columns) and the column vector containing c1, c2, and c3 as its elements.

In summary, to express vector v as a linear combination of vectors v1, v2, and v3 and find Av, we need to know the components of vector v, and then we can set up and solve a system of linear equations to determine the coefficients c1, c2, and c3, and calculate Av using matrix multiplication.

To learn more about linear equations, refer below:

https://brainly.com/question/29739212

#SPJ11

Answer:

e) ab/(a - b)

Step-by-step explanation:

1/x + 1/a = 1/b

now we need to transform this so that we get x = ...

first, let's multiply both sides by x

1 + x/a = x/b

now we subtract x/a from both sides

1 = x/b - x/a

we multiply both sides by a

a = ax/b - x

we multiply both sides by b

ab = ax - bx = x(a - b)

now we divide both sides by (a - b)

ab/(a - b) = x

Answer: Paul's front wheel completed 21,147 full revolutions.

Step-by-step explanation:

The distance traveled by the bike is equal to the circumference of the front wheel times the number of revolutions made by the wheel. The circumference C of a circle is given by the formula C = 2πr, where r is the radius of the circle.

In this case, the radius of the front wheel is 56 cm, so its circumference is:

C = 2πr = 2π(56 cm) ≈ 351.86 cm

To convert the distance traveled by Paul from kilometers to centimeters, we multiply by 100,000:

distance = 75.1 km = 75,100,000 cm

The number of full revolutions N made by the front wheel is therefore:

N = distance / C = 75,100,000 cm / 351.86 cm ≈ 213,470.2

However, we need to round down to the nearest integer since the wheel cannot complete a fractional revolution. Therefore:

N = 21,147

Therefore, Paul's front wheel completed 21,147 full revolutions.

The assertion "H: > 125" can be part of a legitimate statistical hypothesis when accompanied by a corresponding null hypothesis.

We will determine if the assertion "H: > 125" is a legitimate statistical hypothesis and explain why.

A statistical hypothesis is a statement about a population parameter that can be tested using sample data. There are two types of hypotheses: null hypothesis (H0) and alternative hypothesis (H1 or Ha). The null hypothesis is a statement of no effect, while the alternative hypothesis is a statement of an effect or difference.

In this case, the assertion "H: > 125" appears to be an alternative hypothesis, as it suggests that some parameter is greater than 125. However, for it to be a legitimate statistical hypothesis, it must be paired with an appropriate null hypothesis.

For example, if we were testing the mean weight of a certain species of animal, our hypotheses could be as follows:

- Null hypothesis (H0): The mean weight is equal to 125 (μ = 125)
- Alternative hypothesis (H1): The mean weight is greater than 125 (μ > 125)

With this pair of hypotheses, we can conduct a statistical test to determine whether the data supports the alternative hypothesis or not. In conclusion, the assertion "H: > 125" can be part of a legitimate statistical hypothesis when accompanied by a corresponding null hypothesis.

To know more about legitimate statistical hypothesis refer here:

https://brainly.com/question/30893254

#SPJ11

Answer: D. The two rotations map the same image since 350° is a full rotation and 180° + 360° = 540°.

The length of side x in simplest radical form with a rational denominator is[tex]3\sqrt{4.5}[/tex].

An isosceles triangle is a triangle with any two sides that are the same length and angles on opposite sides that are the same size.

The right triangle is isosceles, which indicates that its two legs are the same length. This length should be called "y".

Using the Pythagorean theorem, we know that:

[tex]y^{2}+y^{2}=9^{2}[/tex]

Simplifying this equation:

[tex]2y^{2}=81[/tex]

Dividing both sides by 2:

[tex]y^{2}[/tex] = 40.5

Taking the square root of both sides:

y = [tex]\sqrt{40.5}[/tex]

We can simplify this expression by factoring out a perfect square:

y = [tex]\sqrt{4.5*9}[/tex]

y = [tex]3\sqrt{4.5}[/tex]

Since we know that x has the same length as y, the length of x is also:

x = [tex]3\sqrt{4.5}[/tex]

Therefore, the length of side x in simplest radical form with a rational denominator is[tex]3\sqrt{4.5}[/tex].

know more about triangle visit :

https://brainly.com/question/2773823

#SPJ1

Considering all Martha's instructions for making a cardboard cylinder, the resultant cardboard cylinder is present in above figure.

In mathematics, a cylinder is a three dimensional object with two parallel bases connected at fixed points by curved edges. The distance between the two bases is called the vertical distance and "h" indicates the height. The distance between two circles is called the radius of the cylinder and is defined by "r". It is combination of 2 circles + 1 rectangle :

We have provide the instructions follows by Martha to make a cardboard cylinder and we have to make same cylinder or like as Martha's.

After following the all these necessary instructions for cylinder construction, the resultant cardboard cylinder in present in figure.

For more information about cylinder, visit :

https://brainly.com/question/27440983

#SPJ4

Complete question:

Martha must make a cardboard cylinder, she herself cuts out the bases, cuts the lateral face along a generatrix and extends it on the sheet; make a cylinder like Martha's.

The angle ACB is tan⁻¹(80/a), the range of tan⁻¹(x) is (0, 90) and the time taken to reach the shore is a/30

The measure of ACB can be calculated using the following tangent trigonometry ratio

tan(ACB) = Opposite/Adjacent

So, we have

tan(β) = 80/a

Take the arc tan of both sides

So, we have

β = tan⁻¹(80/a)

So, the angle is tan⁻¹(80/a)

Given that the angle is an acute angle

The range of tan⁻¹(x) for acute angles can be found by considering the values of the tangent function for angles between 0 and 90 degrees.

Since tan(0) = 0 and tan(90) is undefined, the tangent function takes on all positive values in this range.

So, the range of tan⁻¹(x) for acute angles is (0, 90) degrees.

Here, we have

Distance = a

Speed = 30 km/h

The time taken to reach the shore can be calculated using the formula:

time = distance / speed

Substituting the given values, we get:

time = a / 30 km/h

Simplifying this expression, we get:

time = a / 30 hours

Therefore, the time taken to reach the shore is a/30 hours, where a is the distance to the shore in kilometers.

Read more about bearing distance at

https://brainly.com/question/22719608

#SPJ1

The value of P(E ∪ F) is  0.67 so that correct answer is option d.

Given value of the  P(E) = 39⁄100 , P(Fc ) = 53⁄100 , and P(F ∩ Ec ) = 7⁄25, to find P(E ∪ F),

we can use the formula of probability;

P(E ∪ F) = P(E) + P(F) - P(E ∩ F)

step 1:-First, we need to find P(F). Since we know P(Fc) = 53/100, we can find P(F) using, here P(Fc) denotes probability of not happening event F.

P(F) = 1 - P(Fc) = 1 - (53/100) = 47/100

step2:-Next, we need to find P(E ∩ F). We know P(F ∩ Ec) = 7/25. Since Ec is the complement of E, we can use the formula:

P(E ∩ F) = P(F) - P(F ∩ Ec) = (47/100) - (7/25)

To subtract the fractions, we need a common denominator. The least common multiple of 100 and 25 is 100, so we convert (7/25) to (28/100):

P(E ∩ F) = (47/100) - (28/100) = 19/100

step3:-Now we can find P(E ∪ F) using the formula:

P(E ∪ F) = P(E) + P(F) - P(E ∩ F) = (39/100) + (47/100) - (19/100)

P(E ∪ F) = (39 + 47 - 19) / 100 = 67/100

So, the answer is d) 0.67.

learn more about "probability" click here:

https://brainly.com/question/14398287

#SPJ11

Answer:

EG = 75°

Step-by-step explanation:

the secant- secant angle DFQ is half the difference of its intercepted arcs, that is

∠ DFQ = [tex]\frac{1}{2}[/tex] (DQ - EG) , substituting values

35° = [tex]\frac{1}{2}[/tex] (145 - EG ) ← multiply both sides by 2 to clear the fraction

70° = 145 - EG ( subtract 145 from both sides )

- 75 = - EG ( multiply both sides by - 1 )

EG = 75°

Answer:

The expression that can be used to determine the total number of eggs the hen lays for w weeks is:

5.5w

This expression multiplies the average number of eggs laid per week (5.5) by the number of weeks (w) to calculate the total number of eggs laid.

Answer:

(a) Yes, the statement is true. If the null hypothesi is true, we can retain the null. 

(b) Yes, the statement is true

Answer:

(a) Yes, the statement is true. If the null hypothesi is true, we can retain the null. 

(b) Yes, the statement is true