Classify each of the activities below as either a unit level, batch$-$level, product$-$level, or facility$-$level activity.ActivityActivity Classificationa. Various individuals manage the parts inventories.b$.$ A clerk in the factory issues purchase orders for a job.c$.$ The personnel department trains new production workers.d$.$ The factory's general manager meets with other department heads to coordinate plans.e$.$ Direct labor workers assemble products.f$.$ Engineers design new products.g$.$ The materials storekeeper issues raw materials to be used in jobs.h$.$ The maintenance department performs periodic preventive maintenance on general$-$use equipment.