Women in the Labor Force. The Organization for Economic Cooperation and Development (OECD) summarizes data on labor-force participation rates in OECD in Figures. Independent simple random samples were taken of 300 U.S. women and 250 Canadian women. Of the U.S. women, 215 were found to be in the labor force; of the Canadian women, 186 were found to be in the labor force.

a. At the 5% significance level, do the data suggest that there is a difference between the labor-force participation rates of U.S. and Canadian women?

b. Find and interpret a 95% confidence interval for the difference between the labor-force participation rates of U.S. and Canadian women.