Hardigree Insurance Has Collected the Following Information Over the Last

Hardigree Insurance has collected the following information over the last six months. $\begin{array}{ccc}\text { Month }& \text { Units produced } &\text { Total costs }\\\text { March } & 2,000 & \$ 6,700 \\\text { April } & 3,200 & 9,400 \\\text { May } & 2,200 & 7,100 \\\text { June } & 3,000 & 9,500 \\\text { July } & 2,800 & 8,000 \\\text { Auqust } & 2,100 & 6,600\end{array}$ Using the high-low method, how much is the variable cost per unit?

A) $2.25
B) $2.55
C) $2.80
D) $3.14