Thompson Company Had the Following Results of Operations for the Past

Thompson Company had the following results of operations for the past year:
$$\begin{array} { l r r } \text { Sales } ( 16,000 \text { units at } \$ 10 ) & & \$ 160,000 \\\text { Direct materials and direct labor } & \$ 96,000 & \\\text { Overhead (20\% variable) } & 16,000 \\\text { Selling and administrative expenses (all fixed) } & \underline { 3 2 , 0 0 0 } &\underline { ( 144,000 ) } \\\text { Operating income } && \underline { \underline { \$ 16,000}}\end{array}$$
A foreign company (whose sales will not affect Thompson's market) offers to buy 4,000 units at $7.50 per unit.In addition to variable manufacturing costs,selling these units would increase fixed overhead by $600 and selling and administrative costs by $300.If Thompson accepts the offer,its profits will:

A) Increase by $30,000
B) Increase by $ 6,000
C) Decrease by $ 6,000
D) Increase by $ 5,200
E) Increase by $ 4,300