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 p̂ and q̂ 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?