A random sample is selected from a normal population with a mean of and a standard deviation of After a treatment is administered to the individuals in the sample, the sample mean is found to be a....

A random sample is selected from a normal population with a mean of

and a standard deviation of

After a treatment is administered to the individuals in the sample, the sample mean is found to be

a. If the sample consists of
scores, is the sample mean sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with

b. If the sample consists of

scores, is the sample mean sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with

c. Comparing your answers for parts a and b, explain how the size of the sample influences the outcome of a hypothesis test.