For this problem, carry at least four digits after the decimal in your calculations. Answers may vary slightly due to rounding. How hard is it to reach a businessperson by phone? Let p be the...

(a) If you have no preliminary estimate for
p, how many business phone calls should you include in a random sample to be 80% sure that the point estimate p̂ will be within a distance of 0.03 from
p? (Round your answer up to the nearest whole number.)
phone calls


(b) A report states that businesspeople can be reached by a single phone call approximately 15% of the time. Using this (national) estimate for
p, answer part (a). (Round your answer up to the nearest whole number.)
phone calls