Assume that you own a sole proprietorship. Your first-year earnings were $75,000, and your explicit costs were $55,000. If you could have worked at another establishment and earned $25,000, which of the following is true?
a. Your firm earned an economic profit of $20,000
b. Your firm's total implicit costs were $80,000
c. Your firm sustained an economic loss of $5,000
d. Your firm's total costs are $100,000