19. In 2001, the U.S. Department of Labor reported the average hourly earnings for U.S. production workers to be $14.32 per hour (The World Almanac 2003). A sample of wage rates for 75 production workers during 2003 is in the CD file named WageRate. 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.