In the majority of lubricating oil systems for internal combustion engines, the external system includes such parts as _____, _____, _____, and _____. A: engine oil B: sumps C: oil pumps D: oil coolers

Waste oil from the lube oil sumps of machinery may NOT be （）. A: drained into the vessels bilges B: reclaimed for other uses C: held in a slop tank D: purified and then reused