A cost$-$allocation base:

a$.$ links indirect costs to cost objects.

b$.$ traces the direct costs and pools them.

c$.$ serves as a base for determining the period costs.

d$.$ assigns direct costs to cost objects.

Which of the following is true of a job$-$costing system?

a$.$ It is mostly suitable for companies that produce identical products.

b$.$ Job$-$costing systems accumulate costs separately for each product or service.

c$.$ It calculates the per$-$unit cost as the average unit cost that applies to all units produced.