Divide your 135 miles by the miles per gallon (MPG) of the vehicle. So at 20 to the gallon you would need 7 gallons. At 35 to the gallon you would need 3 gallons. It all depends on your average MPG which is affected by wind, hilliness, average road speed, acceleration and braking etc etc.
Impossible to answer ! We would need to know the miles per gallon figure for the vehicle !
That depends on your speed. Do distance, rate and time and you could figure it out.
Figure out the mileage - how many miles do you get per gallon? Take that number and divide it into 731. If you get 28 miles per gallon, it would take you (731 divided by 28 =26.1) about 26 gallons of gas.
The time (hours) required to drive 20 miles is (20) / (speed, in miles per hour)
If you average 60 mph, you can travel 960 miles in 16 hours. Figure two days of driving.
Too many unknown variables to answer. You don't state the MPG figure for the van and, additionally, the weight of the passengers would affect the final figure.
Depends on your speed!
It's roughly 75 miles, so figure an hour and a quarter.
1 hour 20 minutes.
How many miles to the gallon do you get? Divide that number into 575.
40 gallons !
29.16 Gallons.