Can you please help me understand the following problem? Please explain it using the TI84 calculator, as well as the steps. Thanks.

A physical therapist wants to determine the difference in the proportion of men and women who participate in regular sustained physical activity. What sample size should be obtained ifshe

wishes the estimate to be withinfivepercentage points with99% confidence, assuming that

(a)sheuses the estimates of22.4% male and18.5% female from a previousyear?

(b)shedoes not use any priorestimates?

(a)n=

(Round up to the nearest wholenumber.)

(b)n=

(Round up to the nearest wholenumber.)