Given that:
Lake Superior contains 3.0 x 10^15 gallons of water
Firstly, let's know that of 1 gallon;
1 gallon = 0.00375 cubic meter
Then, 3.0 x 10 ^15 = 3.0x10^15 x 3.785 x 10 ^-3
= 3 x 3.785 x 10^15-3
= 11.355 x 10 ^12m^3
Therefore, 11.355x10^12 cubic meters of water are contained in the lake.
