Gray Company produces and sells a single product. The information about their operation for the last month is given below. How many units did they sell during the last month ?

Price : $10.00

Variable Cost Per Unit : $6.00

Fixed Expenses : $3,000

Operating Leverage : 4

A) 1,000 units B) 1,200 units C) 2,000 units D) 1,500 units E) None of above

Answer was A) but I need help with steps as to how and why.