6. How is the t distribution different from the Z distribution?

a. The t distribution is an approximately normal curve, while the Z distribution is perfectly normal.

A and C only

c. The t distribution is flatter than the Z distribution due to a smaller sample size

All of these

b. The t distribution is asymmetrical, that is, it is not a mirror image on each side of the population mean

7. When using a large sample mean with a one-tailed alternative hypothesis and an alpha of .05, the critical score would be:

3.291

1.960

1.65 or 1.645

not enough information given to answer

8.True or False: In the 5 steps of hypothesis testing, to make our rejection decision, we compare step 4 to step 1.

True

False

9.If you want to gain more precision in your confidence interval, what effect would this have on your level of confidence?

your level of confidence would have to decrease (say from 99% to 95%)

your level of confidence would have to increase (say from 95% to 99%)