Using the information in Table 3.10 to determine the

(a) sampling proportions for a stratified random sample selected using proportional allocation.

(b) sample size that will produce a bound on the error of estimation for estimating the mean of ???? = 3.

(c) proportional allocation for the sample size in part

(b) (i.e., the strata sample sizes).

Stratum N SD Cost 123 6,000 20 4 2 5,000 25 2.50 4,000 15 6 15,000