Question

The total amount of fresh water on earth is estimated to be 3.73 x 10^8 km^3. What is this volume in cubic meters? in cubic feet?

Answer 1

One km^3 is 1,000,000,000 m^3=10^9 m^3 hence 3.73 10^8 km^3 is 3.73 10^17 m^3

One meter is 3.28084 feet hence 1 m^3 is (3.28084)^3 feet

Thus 3.73 10^8 km^3 is 3.73*35.315 10^17 = 132 cubic feet

Answer 2

The total amount of fresh water on earth is
`3.73 *10^(8) km^3`

Hence the volume of water
`v= 3.73*10^(8) km^(3)`

we are asked to convert this into cubic metre and cubic feet.

we know that 1 km = 1000 m.

`1 km^3 = [10^3 m]^3`

`1 km^3 = 10^(9) m^(3)`

we have been given
`v = 3.73 *10^(8) km^3`

`v = 3.73 *10^(8) *10^(9) m^(3)`

`v = 3.73*10^(17) m^(3)` [ANS]

Now we have to convert it into cubic feet

we know that one metre = 3.28083 feet

`1 m^(3) =[3.28083feet]^(3)`

`1 m^(3) =35.3143472 feet^(3)`

Hence
`v =3.73*10^(17) m^(3)`

`= 3.73*10^(17) *35.3143472 feet^(3)`

⇒
`v = 131.7225*10^(17) feet^(3)` [ANS]