In the United States in 2010, 30 million people had full-time managerial jobs that paid an average of $1,200 a week and 10 million people had full-time sales jobs that paid an average of $600 a week.

1. Explain why managers are paid more than salespeople.

2. Explain why, despite the higher weekly wage, more people are employed as managers than as salespeople.

3. As more firms offer their goods and services for sale online, how does the market for salespeople change?