Calculate the test statistic z used in testing the following:
a. Ho: p = 0.70 Ha: p > 0.70 with the sample n = 300 and x = 224
b. Ho: p = 0.50 Ha: p < 0.50 with the sample n = 450 and x = 207
c. Ho: p = 0.35 vs Ha: p ≠0.35 with the sample n = 280 and x = 94
d. Ho: p = 0.90 vs. Ha: p_0.90 with the sample n = 550 and x = 508