Assume the total product of three workers is 120 and the total product of four workers is 160. The average product of four workers is ________, and the marginal product of the fourth worker is ________.

A) 10; 40
B) 30; 10
C) 40; 40
D) 160; 40

Marginal Product

The increase in output resulting from a one-unit increase in the amount of a single input while holding other inputs constant.

Average Product

The total output produced per unit of a factor of production, calculated as total product divided by the quantity of the factor used.