A competitive firm produces output using three fixed factors and one variable factor. The firm's short run production function is , where x is the amount of variable factor used. The price of output is $3 per unit and the price of the variable factor is $9 per unit. In the short run, how many units of x should the firm use?
选项:
A:40
B:20
C:19
D:80
发布时间:2024-06-04 01:09:03