8. Suppose you have the opportunity to sell used books and can sell 1 book per hour at a price of $15. The only cost to you is the opportunity cost of your time. For the first 5 hours, the opportunity cost of your time is $10 per hour, But after 5 hours, you value your time at $20 per hour because you have to study. Draw the marginal cost to you of supplying books. Draw in the price you receive for books. How many books will you sell? Calculate your producer surplus.

Fig: 1