I. Elly Industrie s currently manufactures 30,000 units of Part MR24 each month for use in production. T he facilities now used to produce Part MR24 have a fixed monthly cost of $150.000 and a capacity to produce 35,000 units per month. If Elly were to buy part MR24 fr present amount. The variable production costs of Part MR24 are $11 per unit. If Elly industries is able to obtain Part MR24 from an outside supplier at a unit purchase price of $15, the monthly usage at which it will be indifferent between om an outside su d monthly costs would continue at 40% of their purchasing and making Part MR24 is