I WILL MAKE BRAINLIEST PLEASE HELP

Solution here,
dimentions of is 20 in. by 10 in. by 12 in.
i.e. volume of tank=20×10×12=2400 cu. in.
Again,
the tank holds 10 gallons of water
i.e. 10 gallons of water occupies 2400 cu. in.
so, 1 gallon of water occupies 2400/10 cu.in.
=240 cu.in