Suppose that we wish to test H0:u = 80 versus Ha: u > 80, where population standard deviation is known to equal 20. Also, suppose that sample of 100 measurements randomly selected from population has mean equal to 85.
a. Calculate the value of the test statistic z.
b. By comparing z with critical value, test H0 versus Ha at a = .05.
c. Compute the p-value for testing H0 versus Ha.
d. Employ the p-value to test H0 versus Ha at each of a = .10, .05, .01, and .001.
e. How much evidence is there that H0: u = 80 is false and Ha: u > 80 is true?