If your tuition is $8,000 this semester, your books cost $500, you can only work 20 rather than 40 hours per week during the 15 weeks you are taking classes and you make $20 per hour, and your rent is $5,000 this semester, what is your opportunity cost of attending college this semester after paying tuition and buying textbooks? Assume that rent will remain the same even if you do not go to college. Also assume you your tuition is non-refundable but you can sell your books for a total of $400.