Suppose we are using the sample size formula in the box on page 313 to find the sample size needed to make the margin of error in a confidence interval for p equal to E. In each of the following situations, explain what value of p would be used in the formula for finding n:
a. We have no idea what value p is— it could be any value between 0 and 1.
b. Past experience tells us that p is no more than .3.
c. Past experience tells us that p is at least .8.