Feargus is an agriscientist who has begun working on a farm. He can't find any maintenance records for a tractor he wants to use. He asks a coworker, Nick, if the oil has been changed recently, and Nick says, "Yeah, I checked it a couple weeks ago. There's plenty of oil in there." What should Feargus do?
assume the tractor is fine to use
check the oil level himself to verify what Nick told him
change the oil if he can't tell how long ago it was last changed
inspect the tractor for signs of oil leakage