Use the Following to Answer Questions :
Figure and Table

Use the following to answer questions :
Figure and Table: Variable,Fixed,and Total Costs $$\begin{array} { l c c c c c } \begin{array} { l } \text { Points on } \\\text { Graph }\end{array} & \begin{array} { c } \text { Quantity } \\\text { of Labour } \\\text { (workers) , } \boldsymbol { L }\end{array} & \begin{array} { c } \text { Quantity } \\\text { of Wheat } \\\text { (bushels) , } \boldsymbol { Q }\end{array} & \begin{array} { c } \text { Variable } \\\text { Cost, } \\\boldsymbol { V C }\end{array} & \begin{array} { c } \text { Fixed } \\\text { Cost, } \\\boldsymbol { F C }\end{array} & \begin{array} { c } \text { Total Cost, } \\\boldsymbol { T C } = \boldsymbol { F C } + \boldsymbol { V } \boldsymbol { C }\end{array} \\\hline A & 0 & 0 & \$ 0 & \$ 400 & \$ 400 \\B & 1 & 19 & 200 & 400 & 600 \\C & 2 & 36 & 400 & 400 & 800 \\D & 3 & 51 & 600 & 400 & 1000 \\E & 4 & 64 & 800 & 400 & 1200 \\F & 5 & 75 & 1000 & 400 & 1400 \\G & 6 & 84 & 1200 & 400 & 1600 \\H & 7 & 91 & 1400 & 400 & 1800 \\I & 8 & 96 & 1600 & 400 & 2000\end{array}$$
-(Figure and Table: Variable,Fixed,and Total Costs) Use Figure and Table: Variable,Fixed,and Total Costs.The marginal cost of increasing production from 84 to 91 kilograms of wheat is:

A) $13.00.
B) $19.78.
C) $22.22.
D) $28.57.