1. 6. Suppose a small business takes in a monthly revenue of $200,000. Labor, rental, energy, and other purchased input costs come to a total of $170,000. The entrepreneur's monthly opportunity cost of her time invested in the business is $5,000 (this is what she could earn working elsewhere), and the entrepreneur could get a return of $5,000 each month if she sold her business and invested the net proceeds in a financial asset such as a treasury bond. Her monthly economic profit equals O a. $200,000 O b. $30,000 O c. $190,000 O d. $20,000