Answer:
21r +3
Step-by-step explanation:
3(7r + 1) =
Distribute
3*7r +3*1
21r +3
1) + $12, since it is a profit
2) -1440 ft, since it is below the sea level
3) - 22°F, since it is below
4) + 31 yards, since it is a gain.
It took about 0.66 hour, which is basically 40 minutes.