14. A random sample of n = 9 scores is selected from a normal population with a mean of p = 100. After a treatment is administered to the individuals in the sample, the sample mean is found to be M = 106. a. If the population standard deviation is o = 10, is the sample mean sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with a = .05. b. Repeat part a, assuming a one-tailed test with a = .05. c. If the population standard deviation is o = 12, is the sample mean sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with a = .05. d. Repeat part c, assuming a one-tailed test with a = .05. e. Comparing your answers for parts a through d, ex- plain how the magnitude of the standard deviation and the number of tails in the hypothesis influence the outcome of a hypothesis test