Alternative 3: Start to produce plastic rings in September Because RMG needs to prepare for the plastics production until September. For the short run, we assume no capacity expansion, so we will exclude the fixed OH costs estimated by the controller and include the additional fixed OH incurred by the acquisition of molds and tooling To calculate the additional fixed OH, i. e. molds and tooling, we assume the useful life of this equipment is 5 years. One can also assume that the demand for the plastic rings will start with 10% of the current demand for steel rings. The variable OH cost is 80% of direct labor costs = 15.60*80% = The annual demand for the plastic rings: Annual demand for the plastic rings = 690units/wk * 53wks * 10% =3657 units The additional OH cost per 100 plastic Cost per 100 units= (Acquisition cost/( useful life*annual demand )) * 100 =10,000*100/(5*3657) =$54.69