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
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?
A.20
B.80
C.19
D.40
正确答案:40