As a Manufacturer of Guitars, a Major Corporation Wants to Estimate

Short Answer

As a manufacturer of guitars, a major corporation wants to estimate the proportion of guitar players who are right-handed.How many golfers must be surveyed if they want to be within 0.02, with a 95% confidence?
a.
Assume that there is no prior information that could be used as an estimate of.
b.
Assume that the manufacturer has an estimate offound from a previous study, which suggests that 75% of guitar players are right-handed.