MBA 10-2 Unit cost analysis Hathaway Trophies Inc. uses a job order cost system for determining the cost to manufac- ture award products (plaques and trophies). Among the company's products is an engraved plaque that is awarded to participants who complete an executive education program at a local university. The company sells the plaques to the university for $50 each. Each plaque has a brass plate engraved with the name of the participant. Engraving requires approximately 30 minutes per name. Improperly engraved names must be redone. The plate is screwed to an oak backboard. This assembly takes approximately 6 minutes per unit. Improper assembly must be redone using a new oak backboard. During the first half of the year, the university had two separate executive education classes. The job cost sheets for the two separate jobs indicated the following information: Units Job Cost Job 05-1 May 2 Cost per Unit Direct materials: Wood $ 7.50/unit Brass 4.00/unit Engraving labor 20.00/hr. Assembly labor 15.00/hr. Factory overhead 3.00/hr. Total Plaques shipped Cost per plaque (rounded to nearest cent) 75 units 75 units 40 hrs 7.5 hrs. 45 hrs. $ 562.50 300.00 800.00 112.50 135.00 $1,910.00 75 $ 25.47 Units Job Cost Job 08-11 August 25 Cost per Unit Direct materials: Wood $ 7.50/unit Brass 4.00/unit Engraving labor 20.00/ht Assembly labor 15.00/hr. Factory overhead 3.00/hr. Total Plaques shipped Cost per plaque (rounded to nearest cent) 85 units 85 units 50 hrs. 8 hrs. 48 hrs. $ 63750 340.00 1,000.00 120.00 144.00 $2,24150 80 $ 28.02 a. Why did the cost per plaque increase from $25.47 to $28.02? b. Based upon unit costs, what is an area of concern for Hathaway Trophies, Inc