19. Weight average costing method and first in first out costing method give the same results (Assigning costs to finished goods and transferred out).

a. If they have the same added units

b. If there are not beginning inventories.

c. If there are not ending inventories.

d. If there are not units transferred out.

20. Sunk costs are past costs.

True or False

21. An opportunity cost is the benefit sacrificed in favoring one alternative over another.

True or False