Which of the following statement(s) is(are) correct? o In Absorption costing all the variable cost of production including direct material, direct labor, and variable manufacturing overheads are assigned to products. o Job-order costing ststems are used when companies produce many similar types of products. o A normal costing system assigns overhead costs to products by multiplying the actual overhead rate by the actual amount of the allocation base. o A unit product cost represents the incremental cost that would be incurred if another unit were produced. o Manufactring overhead is an indirect cost. o The predetermined overhead rate tends to remain stable from period to period