Gargymal Company Would Like to Estimate the Variable and Fixed

Gargymal Company would like to estimate the variable and fixed components of its electrical costs and has compiled the following data for the last five months of operations:
$\begin{array} { | l | r | r | } \hline & \text { Machine Hours } & \text { Electrical Cost } \\\hline \text { August } & 1,000 & \$ 1,620 \\\hline \text { September } & 900 & 1,510 \\\hline \text { October } & 1,500 & 1,870 \\\hline \text { November } & 2,000 & 1,950 \\\hline \text { December } & 1,300 & 1,730 \\\hline\end{array}$


-Using the high-low method,the estimated variable cost per machine hour for electricity is closest to which of the following?

A) $0.40 per hour.
B) $0.98 per hour.
C) $1.68 per hour.
D) $2.50 per hour.