Unit 10 | lesson 5 lesson checkpoint: show what you know question navigator choose the answer. 2. (1 pt) which answer is the most reasonable estimation? gwen owns an oil-change station. she estimates that she uses 18 cases of motor oil a day. each case has 24 one-quart bottles of motor oil. about how many quarts of oil does gwen use in a day? a. about 600 b. about 400 c. about 200 d. about 40 question resources