Potlatch Company Manufactures Sonars for Fishing Boats An Offer Has Come in for a One-Time Sale of $400.Potlatch

Potlatch Company manufactures sonars for fishing boats.Model 100 sells for $400.Potlatch produces and sells 6,000 units per year.Cost data are as follows: $$\begin{array} { | l | r | l | } \hline \text { Variable manufacturing } & \$ 105 & \text { per unit } \\\hline \text { Variable selling and administrative } & \$ 7 & \text { per unit } \\\hline \text { Fixed manufacturing } & \$ 280,000 & \text { per year } \\\hline \text { Fixed selling and administrative } & \$ 130,000 & \text { per year } \\\hline\end{array}$$ An offer has come in for a one-time sale of 300 units at a special price of $130 per unit.The marketing manager says that the sale will not affect the company's regular sales activities,and that it will not require any variable selling and administrative costs.The production manager says that there is plenty of excess capacity and the sale will not impact fixed costs in any way.What is the effect of this deal on operating income?

A) Operating income increases by $400.
B) Operating income increases by $2,100.
C) Operating income decreases by $7,500.
D) Operating income increases by $7,500.