Table 7-2 Shows the Combinations of Labor and Capital That

Table 7-2 shows the combinations of labor and capital that are used to produce various levels of output
Table 7-2 $$\begin{array} { | c | c | c | c | } \hline \text { Units of capital } & \text { Units of labor } & \text { Total Product } & \text { Marginal product of labor } \\\hline 2 & 0 & 0 & - \\\hline 2 & 1 & 20 & 20 \\\hline 2 & 2 & 44 & 24 \\\hline 2 & 3 & 68 & 24 \\\hline 2 & 4 & 90 & 22 \\\hline 2 & 5 & 78 & - 12 \\\hline\end{array}$$
-Refer to Table 7-2.Based on the input-usage ratio,we can say that the firm is operating _____.

A) at an economic loss
B) in the short-run
C) in a constant-cost industry
D) in the long-run