This cannot be answered properly without knowing what your speed is.
1 hour 21 minutes @65 mph
21 minutes.
Approximately 20 minutes.
21 minutes, 13.85 seconds
It would take .525 of an hour to drive 21 miles at 40mph without traffic, or a little over half an hour.
That would depend on the price of the fuel
21 hours 40 minutes.
1300 miles, 21 hours
10 hours 21 minutes.
22 minutes 54.5 seconds.
.42 hours
1 hour 21 minutes.