Lefties Find the sample size needed to estimate the percentage of California residents who are left-handed. Use a margin of error of three percentage points, and use a confidence level of 99%.

a. Assume that pn and qn are unknown.

b. Assume that based on prior studies, about 10% of Californians are left-handed.

c. How do the results from parts

(a) and

(b) change if the entire United States is used instead of California?