Amazon has some job openings. Lots of them. The company said Wednesday that it's looking to fill more than 50,000 positions across the U.S. It's planning to make thousands of offers on the spot on Aug. 2, when it opens the doors to potential hires at 10 Amazon.com Inc. shipping sites. There will be more than 10,000 part-time jobs available at sorting centers, and some supporting and managerial positions. The labor market is growing tight with back-to-school and holiday shopping around the corner. Others will be competing for those same hires. The unemployment rate is 4.4 percent, near a 16-year low, yet the average hourly pay rose just 2.5 percent in the past year. The last time unemployment was this low, wages were rising at roughly a 4 percent rate.