Exercise $17-9($Algo$)$ Allocating overhead using plantwide rate and departmental rates LO P$1,$ P$2$ Laval produces lighting fixtures. Budgeted information for its two production departments follows. The departments use machine hol $($MH$)$ and direct labor hours $($DLH$).$ Laval reports the following for one of its products, a desk lamp. Required: $1.$ Determine the plantwide overhead rate using $186,250$ direct labor hours as the allocation base. $2.$ Determine the overhead cost per unit for the desk lamp using the plantwide overhead rate. $3.$ Compute departmental overhead rates based on machine hours in the Fabricating department and direct labor hours in the Assembly department. $4.$ Determine the overhead cost per unit for the desk lamp using the departmental overhead rates.