Exhibit 7-8 Costs Schedules for Producing Pizza -By Filling in the Blanks in Exhibit 7-8, the Marginal

Exhibit 7-8 Costs schedules for producing pizza $\begin{array}{|c|c|c|c|c|}\hline\text { Pizzas } & \begin{array}{c}\text { Fixed } \\\text { Cost }\end{array} & \begin{array}{c}\text { Variable } \\\text { Cost }\end{array} & \begin{array}{c}\text { Total } \\\text { Cost }\end{array} & \begin{array}{c}\text { Marginal } \\\text { Cost }\end{array} \\\hline 0 & \$ & \$ & \$ & \$ \\1 & & 5 & & \\2 & & 13 & & \\3 & & && 10 \\4 & 100 & &140 & \\5 & & &&20 \\6 & &85 & & \\7 & & & 215 \\\hline\end{array}$
-By filling in the blanks in Exhibit 7-8, the marginal cost of the fourth pizza is shown to be equal to:

A) $10.
B) $15.
C) $17.
D) $23.
E) $40.