Just one male betta, but you should consider a proper betta set up which can have 2 to 2.5 gallons for the one fish.
id say 15 fish
half a mile
length and width for a 55 gallon fish tank
The rule of thumb is usually a gallon per fish, so six gallons would be good. If the fish are on the large side (like a goldfish), then a seven gallon tank would be ideal.
1.5 hours
This is simply funny if it really means a fish tank.About 1025.5 for a standard 100 gallon fish tank if the beers are 12 fl oz.Remember fish tank gallon sizes are measured by outside dimensions.
Only 1. Usually a Betta is all that is kept in a 3 gallon tank
About 60.566 liters to fill a 16-gallon gas tank.
depends on the fishes size
one
one
29 miles per gallon on a 25 gallon tank is 25*29 = 725 miles per tank. So one [partial] fill will be enough.