Suppose you earn $14 an hour and every day you go to lunch at your favorite restaurant, Café Excel, where you spend 30 minutes in transit and waiting for a table, then spend 30 minutes eating and pay $16 for lunch. Suppose further you get a raise to $20 an hour and simultaneously Café Excel has a special allowing you to pay only $12 for lunch. What is the difference in the full price of lunch after your raise? Explain thoroughly.