A report in a research journal states that the average weight loss of people on a certain drug is 17 lbs with a margin of error of ±3 lbs with confidence level C = 95%. (a) According to this...

A report in a research journal states that the average weight loss of people on a certain drug is 17 lbs with a margin of error of ±3 lbs with confidence level C = 95%.

(a) According to this information, the mean weight loss of people on this drug, μ, could be as low as ________ lbs.

(b) If the study is repeated, how large should the sample size be so that the margin of error would be less than 1.5 lbs? (Assume σ= 6 lbs.)