$1.$ Product costs consist of $\_\_\_\_\_\_\_\_.$

a$.$ direct materials

b$.$ direct labor

c$.$ factory overhead

d$.$ All of these choices are correct.

$2.$ All of the following are common methods of allocating factory overhead to products except the $\_\_\_\_\_\_\_\_\_\_$ method.

a$.$ single plantwide rate

b$.$ multiple production department rate

c$.$ activity$-$based costing

d$.$ inventory costing