(4 points) Identify the critical t. An independent random sample is selected from an approximately normal population with unknown standard deviation. Find the degrees of freedom and the critical t value t∗ for the given sample size and confidence level. Round critical t values to 4 decimal places.

a)

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.05,4)"

And for this case the critical value would be

b)

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.025,12)"

And for this case the critical value would be

c)

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.01,21)"

And for this case the critical value would be

d)

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.005,14)"

And for this case the critical value would be

Step-by-step explanation:

Part a

n = 5 , Conf. =0.90

For this case the degrees of freedom are given by:

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.05,4)"

And for this case the critical value would be

Part b

n = 13 , Conf. =0.95

For this case the degrees of freedom are given by:

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.025,12)"

And for this case the critical value would be

Part c

n = 22 , Conf. =0.98

For this case the degrees of freedom are given by:

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.01,21)"

And for this case the critical value would be

Part d

n = 15 , Conf. =0.99

For this case the degrees of freedom are given by:

For this case the significance level is given by and the and for this case we can ue the following code:

"=-T.INV(0.005,14)"

And for this case the critical value would be

77

step-by-step explanation:

x/3-10=8

x/3=18

x=48