Suppose independent random samples from the ???? and ???? populations have been selected. Determine the estimated standard error of ˆ???????? − ˆ???????? when

(a) ???????? = 85, ???????? = 67, ˆ???????? = 0.58, and ˆ???????? = 0.48.

(b) ???????? = 220, ???????? = 248, ˆ???????? = 0.77, and ˆ???????? = 0.84.

(c) ???????? = 180, ???????? = 220, ˆ???????? = 0.13, and ˆ???????? = 0.09.