Which of the following are true regarding activity-based costing

a. A primary goal of using \(A B C\) is a more useful allocation of manufacturing overhead to product lines.

b. Under ABC, direct labor hours are never used to allocate overhead costs to activity pools or product lines.

c. The use of \(A B C\) is indicated when it is suspected that each of a firm's product lines consumes approximately the same amount of overhead resources but the current allocation scheme assigns each line a substantially different amount.

d. \(\mathrm{ABC}\) can be used in conjunction with job order costing.