A researcher conducts a hypothesis test using a sample of n = 40 from an unknown population. What is the df value for the t statistic? a. 38
b. 39
c. 40
d. 41

Correct option: b 39.

Step-by-step explanation:

A one-sample (or one mean) t-test is applied to test whether the population-parameter is significantly different from some hypothetical value.

The degrees of freedom of the t-test is:

df = n - 1

It is provided that the sample size is, n = 40.

Compute the degrees of freedom as follows:

df = n - 1

   = 40 - 1

   = 39

Thus, the correct option is b.

the answer is 13

step-by-step explanation:

5*5=25

12*12=144

25+144=169

169^2=13