A manufacturer of golf equipment wants to estimate , the proportion of all golfers who are left-handed.

4. Assume that there is no available information that could be used as an estimate of . How many golfers must be surveyed so that the sample proportion has a margin of error of 0.03 with 95% confidence?

A. 1067

B. 1067.11

C. 1066

D. 1068

5. Assume that an estimate of found from a previous study is 15%. How many golfers must be surveyed so that the sample proportion has a margin of error of 0.05 with 90% confidence?

A. 139

B. 138.007

C. 137

D. 138