Pam runs a shoeshine stand at the airport. Pam has no skills, no job expereince, and no alternative employment. Entrepreneurs in the shoeshine stand business earn $20,000 a year. Pam pays the rent of $2,500 a year, and her total revenue is $16,000 a year. She borrowed $700 at 15 percent a year to buy equipment. At the end of one year, Pam was offered $500 for her business and all its equipment.

Pam's explicit and implicit costs are ___ $