Sam Sleepresearcher hypothesizes that people who are allowed to sleep for only six hours will score significantly lower than people who are allowed to sleep for eight hours on a cognitive skills test. He randomly selects sixteen participants into his sleep lab and then randomly assigns them to one of two groups. In group 1, he has participants sleep for eight hours and in the other group (group 2) he has them sleep for six. The next morning he administers a cognitive ability test (CAT) to all participants. Scores on the CAT range from 1-9 with high scores representing better performance.

CAT scores
8 hours sleep (group 1)	6 hours sleep (group 2)
8	3
7	1
5	4
3	5
5	6
8	4
3	1
9	2

Question 4 of 272 Points

What statistical analysis should Sam use to test his hypothesis?

A.

One-Sample T-Test

B.

Two-Sample T-Test

C.

Paired T-Test

D.

Two-Sample Z-Test

Question 9 of 272 Points

What statistical analysis should be conducted to determine if the mean difference in accidents before and after the modification is statistically significant?

A.One-Sample T-Test

B.Two-Sample T-Test

C.Paired T-Test

D.Two-Sample Z-Test