CONVERSION costs at a car factory include: a.line employee payroll, factory supervision, factory depreciation, R&D engineer payroll, testing materials, distribution warehouse depreciation. b.engines, bodywork, line employee payroll c.line employee payroll, auto lubricants, equipment depreciation, factory supervision, factory maintenance. d.body motors, line employee payroll, supervision, plant insurance, design engineer, factory light, sales equipment depreciation, freight on merchandise sold (transportation out)