Given a population standard deviation of 12, answer the following two questions. 4) Calculate the standard deviation of WORK: ANSWER the mean ( 0,4 given the following N, = N. = two sample sizes (show all your work N, = N. = and round to two decimal places): N. = 20 N. = 70 5) How does the sample size change the standard error of the mean? What does this mean for statistical power? Calculate the critical degrees of freedom and identify the critical values for the following tests, using p = .05 and the tables in your e-book for all scenarios (do NOT round). Then, state whether the null hypothesis would be rejected or failed to be rejected 6) Single sample t-test: df= ANSWER critical t = ANSWER Reject H: two-tailed, N = 20, t = 2.05 7) Single sample t-test: df= ANSWER critical t = ANSWER one-tailed, N = 20, t = Fail to Reject H.: 2.05 8) Pearson's r correlation: df= ANSWER critical t = ANSWER Fail to Reject H.: two-tailed, N = 15, r = 0.47 9) Pearson's r correlation: df= ANSWER critical t = ANSWER | Reject HE: one-tailed, N = 15, r = 0.47 A company decides to offer a monetary incentive for employees who log a specified number of hours spent exercising in an attempt to improve employee health. The average health score (higher = better) of the 75 employees who logged enough hours was 87. The mean health score for all