Pam runs a shoeshine stand at the airport. Pam has no skills, no job experience, and no alternative employment. Entrepreneurs in the shoeshine stand business earn $16,000 a year. Pam pays the rent of $2,000 a year, and her total revenue is $17,000 a year She borrowed $800 at 10 percent a year to buy equipment At the end of one year, Pam was offered $600 for her business and all its equipment What are Pam's explicit costs, implicit costs, and economic profit? Pam's explicit costs are $