Schedule of Activity Costs Quality Control Activities Activity Cost Process audits $49,100 Training of machine operators 26,000 Processing returned products 17,700 Scrap processing (disposal) 26,200 Rework 5,700 Preventative maintenance 27,400 Product design 40,000 Warranty work 6,300 Finished goods inspection 22,100 From the provided schedule of activity costs, determine the non-value-added costs. Oa. $220,500 Ob. $55,900 Oc. $111,700 Od. $49,600