The U.S. Department of Labor reported the average hourly earnings for U.S. production workers to be $14.32 per hour in 2001 (The World Almanac, 2003). A sample of 75 production workers during 2003 showed a sample mean of $14.68 per hour. Assuming the population standard deviation σ = $1.45, can we conclude that an increase occurred in the mean hourly earnings since 2001? Use α = .05.