Using the large sample confidence interval formula for ???????? − ????????, compute a

(a) 95% confidence interval for ???????? − ???????? when ???????? = 50, ???????? = 50, ˆ???????? = 0.32, and

ˆ???????? = 0.38.

(b) 98% confidence interval for ???????? − ???????? when ???????? = 120, ???????? = 150, ˆ???????? = 0.48, and ˆ???????? = 0.44.

(c) 95% confidence interval for ???????? − ???????? when ???????? = 250, ???????? = 225, ˆ???????? = 0.56, and ˆ???????? = 0.46.

(d) 95% confidence interval for ???????? − ???????? when ???????? = 550, ???????? = 450, ˆ???????? = 0.78, and ˆ???????? = 0.88.