Answer:
20 days
Explanation:
Subtract 1.5 gallons from 14 gallons to obtain the number of days the car will run without the warning light going on: 12.5 gallons.
Dividing this result by 0.6 gallons/day, we get
12.5 gal
------------------- = 20.82 days. Round this down to 20 days. (We're not
0.6 gal/day dealing in partial days.)