Schedule of Activity Costs Quality Control Activities Activity Cost Process audits $49,500 Training of machine operators 27,500 Processing returned products 20,700 Scrap processing (disposal) 24,500 Rework 8,100 Preventative maintenance 28,100 Product design 41,600 Warranty work 8,600 Finished goods inspection 23,200 From the provided schedule of activity costs, determine the appraisal costs. Oa. $169,900 Ob. $49,500 Oc. $117,900 Od. $72,700