question #7 A Monopoly firm sells 600 units of a product per month. The firm faces a constant marginal cost of $15. In addition, the firm has fixed costs of $900 per month. The firm charges $40 for each unit of its product. If a regulator wants the monopoly to charge a socially optimal price, the firm will be required to charge $ per unit. Please input a numerical value without the $ sign your answer. If the answer is $30, please input 30. Numeric Resp