In developing a sampling plan for estimating the difference between the means ????????

and ???????? (i.e., ???????? − ????????), suppose the goal is to minimize the bound on the error of estimation for an fixed overall sample size of ???? = 150. Determine the individual sample sizes ???????? and ???????? when

(a) ????̇ ???? = 30 and ????̇ ???? = 50.

(b) ????̇ ???? = 5 and ????̇ ???? = 2.

(c) ????̇ ???? = 80 and ????̇ ???? = 60.