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 for the given sample size and confidence level. (a) n = 6, CL = 90% (b) n = 21, CL = 98% (c) n = 29, CL = 95% (d) n = 12, CL = 99%

given below

Step-by-step explanation:

Given that an independent random sample is selected from an approximately normal population with unknown standard deviation.

To find the degrees of freedom and the critical t-value for the given sample size and confidence level

degrees of freedom=n-1

Critical t can be got from the t table in internet

a) degree of freedom = 5

Critical 90% is 1.833

b) degree of freedom = 20

Critical 98% is 2.528

c) degree of freedom = 28

Critical 90% is 1.645

d) degree of freedom = 10

Critical 99% is 3.169