To evaluate the effect of a treatment, a sample is obtained from a population with a mean of m 5 40, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M 5 44.5 with a variance of s 2 5 36.

a. If the sample consists of n 5 4 individuals, are the data sufficient to conclude that the treatment has a significant effect using a two-tailed test with a 5 .05?

b. If the sample consists of n 5 16 individuals, are the data sufficient to conclude that the treatment has a significant effect using a two-tailed test with a 5 .05?

c. Comparing your answers for parts a and

b, how does the size of the sample influence the outcome of a hypothesis test?