Let's say our company makes frisbees. How would you categorize our cost for the plastic that we use to make the frisbees? Also, assume that we have a large automated machine that stamps out these frisbees, and every day or so someone in the plant needs to add a quart of special oil to this machine to keep it running properly. Each month we spend about $125 to purchase a new drum of this lubricating material. How would you categorize the expense for this oil? Is it considered a "Direct Material" cost??