In Applying the High-Low Method, What Is the Unit Variable

In applying the high-low method, what is the unit variable cost? $\begin{array}{llr}\text { Month}&\text { Miles }&\text {Total Cost }\\\hline \text { January } & \overline{80,000} & \$ 144,000 \\\text { February } & 50,000 & 120,000 \\\text { March } & 70,000 & 141,000 \\\text { April } & 90,000 & 195,000\end{array}$

A) $2.16
B) $1.88
C) $2.40
D) Cannot be determined from the information given.