The article "College Graduates Break Even by Age 33" (USA Today, September 21, 2010) reported that 2.6% of college graduates were unemployed in 2008 and 4.6% of college graduates were unemployed in 2009. Suppose that the reported percentages were based on independently selected representative samples of 500 college graduates in each of these two years. Construct and interpret a 95% confidence interval for the difference in the proportion of college graduates who were unemployed in these two years.