last year walter paid $25,000 for supplies and had revenue of $60,000. walter asked tyler the accountant and greg the economist to calculate his painting business's costs. a. tyler says his costs are $25,000, and greg says his costs are $65,000. b. tyler says his costs are $25,900, and greg says his costs are $66,500. c. tyler says his costs are $66,500, and greg says his costs are $66,500. d. tyler says his costs are $75,000, and greg says his costs are $41,500.