Presented Below Is the Production Data for the First Six

Presented below is the production data for the first six months of the year for the mixed costs incurred by Strongsville Company. $$\begin{array} { l l l } \text { Month } & \text { Cost } & \text { Units } \\\text { January } & \$ 7,500 & 4,000 \\\text { February } & 13,000 & 6,500 \\\text { March } & 10,500 & 8,000 \\\text { April } & 12,700 & 10,500 \\\text { May } & 13,500 & 12,000 \\\text { June } & 10,850 & 9,000\end{array}$$ Strongsville Company uses the high- low method to analyze mixed costs. The variable cost per unit is:

A) $1.25
B) $1.31
C) $0.132
D) $0.75