Back porch company manufactures lawn chairs using an activity-based costing system to allocate all manufacturing conversion costs. the following information is provided for the month of june: activityestimated indirect activity costsallocation baseestimated quantity of allocation basematerials handling$12,000number of parts12,000 partsassembling$16,800number of parts12,000 partspackaging$4,500number of lawn chairs1,500 lawn chairseach lawn chair consists of 8 parts; the total direct materials cost per lawn chair is $10.00.what is the total manufacturing cost per lawn chair? a) $32.20b) $19.20c) $22.20d) $29.20