Dear Colleagues, The answer for this question is $ 8,000, but I don't know how it comes - please help me if any body knows how to answer. Richardson Motors uses ten units of Part Number T305 each month in the production of large diesel engines. The cost to manufacture one unit of T305 is presented below. Direct Materials $2,000 Material handling(20% of direct material cost) $400 Direct labor $16,000 Manufacturing overhead (150% of direct labor) $24000 ---------------- Total manufacturing cost $42,400 Material handling, which is not included in manufacturing overhead, represents the direct variable costs of the Receiving Department that are applied to direct materials and purchased components on the basis of their cost. Richardson's annual manufacturing overhead budget is one-third variable and two-thirds fixed. Simpson Castings, one of Richardson's reliable vendors, has offered to supply T305 at a unit price of $30,000. Assume the rental opportunity does not exist and Richardson Motors could use the idle capacity to manufacture another product that would contribute $104,000 per month. If Richardson chooses to manufacture the ten T305 units in order to maintain quality control, Richardson's opportunity cost is $36,000. $8,000. $(96,000). $(40,000).