8.65 Union, Yes! A sampling of political candi- dates-200 randomly chosen from the West and 200 from the East was classified according to whether the candidate received backing by a national labour union and whether the candidate won. In the West, 120 win- ners had union backing, and in the East, 142 winners were backed by a national union. Find a 95% confi- dence interval for the difference between the propor- tions of union-backed winners in the West versus the East. Interpret this interval.