Given the Table Below,if Capital Is Fixed at Two Units,what

Multiple Choice

Given the table below,if capital is fixed at two units,what is the marginal product of the fourth unit of labor? $$\begin{array}{l}\quad\quad\quad\quad\quad\text { Units of Capital }\\\begin{array} { c c c c c } \hline & & 1 & 2 & 3 \\\text { Units } & 1 & 80 & 100 & 120 \\\text { of } & 2 & 180 & 220 & 260 \\\text { Labor } & 3 & 270 & 330 & 390 \\& 4 & 340 & 420 & 500 \\& 5 & 390 & 490 & 590 \\& 6 & 410 & 530 & 650\end{array}\end{array}$$ Amount of total output produced from various combinations of labor and capital.

A) 60
B) 80
C) 100
D) 420
E) none of the above