$21)$ Rivera Company manufactured two products, A and B$,$ during April. For purposes of product costing, an overhead rate of $$2\mathrm{.}00$ per direct$-$labor hour was used, based on budgeted annual factory overhead of $$500,000$ and $250,000$ budgeted annual direct$-$labor hours, as follows:

Budgeted Overhead Budgeted Hours

Department $1$ $ $300,000200,000$

Department $2200,00050,000$

$ $500,000250,000$

The number of labor hours required to manufacture each of these products was:

Product A Product B

In Department $131$

In Department $213$

Total $44$

During April, production units for products A and B were $1,000$ and $3,000,$ respectively.

Required:

$(1)$ Using a plantwide overhead rate, what are total overhead costs assigned to products A and B$,$ respectively?

$(2)$ Using departmental overhead rates, what are total overhead costs assigned to products A and B$,$ respectively?

$(3)$ Assume that materials and labor costs per unit of Product B are $$10$ and that the selling price is established by adding $40\%$ of total costs to cover profit and selling and administrative expenses. What difference in selling price would result from the use of departmental overhead rates?