Table 18-1 -Refer to Table 18-1

Table 18-1 $$\begin{array} { | c | c | c | c | c | c | } \hline \begin{array} { c } \text { Number of } \\\text { Workers }\end{array} & \text { Output } & \begin{array} { c } \text { Marginal Product } \\\text { of Labor }\end{array} & \begin{array} { c } \text { Value of Margina1 } \\\text { Product of Labor }\end{array} & \text { Wage } & \text { Marginal Profit } \\\hline 0 & 0 & & & & \\\hline 1 & 100 & & \$ 1000 & \$ 500 & \$ 500 \\\hline 2 & & 80 & \$ 800 & \$ 500 & \\\hline 3 & & 60 & & \$ 500 & \$ 100 \\\hline 4 & 280 & & & \$ 500 & \\\hline 5 & & 20 & & & \\\hline\end{array}$$ $\begin{array}{|l|l|l|l|l|l|}\hline\begin{array}{l}\text { Number of } \\\text { Workers }\end{array} & \text { Output } & \begin{array}{l}\text { Marginal Product of } \\\text { Labour }\end{array} & \begin{array}{l}\text { Value of Marginal } \\\text { Product of Labour }\end{array}&\text { Wage }&\text { Marginal Profit } \\\hline &0&0\\\hline 1 & 25 & 25 & \$ 125 & \$ 40 & \$ 85 \\\hline 2 & 45 & 20 & \$ 100 & \$ 40 & \$ 60 \\\hline 3 & 60 & 15 & \$ 75 & \$ 40 & \$ 35 \\\hline 4 & 70 & 10 & \$ 50 & \$ 40 & \$ 10 \\\hline 5 & 75 & 5 & \$ 25 & \$ 40 & -\$ 15 \\\hline\end{array}$
-Refer to Table 18-1.What is the fourth worker's contribution to total revenue?

A) -$15
B) $10
C) $25
D) $50