Question

Earth has a surface area of 197 million square miles. Convert this area into each of the following units.

(a.) square kilometers
(b.) square megameters
(c.) square decimeters

Answer 1

Answers:

a)
`510,225,121.4 km^(2)`

We know the Earth's surface area in square miles is:

`197000000 mi^(2)`

On the other hand, we know
`1 mi=1.60934 km`.

Then:

`197000000 mi^(2) ((1.60934 km)^(2))/(1 mi^(2))=510,225,121.4 km^(2)`

b)
`510.225 Mm^(2)`

In this part, we can work with the obtained value in part a:

`510,225,121.4 km^(2)`

And knowing
`1 km=0.001 Mm`

Hence:

`510,225,121.4 km^(2) ((0.001 Mm)^(2))/(1 km^(2))=510.225 Mm^(2)`

c)
`5.1022(10)^(16) dm^(2)`

Knowing
`1 Mm=10^(7) dm`:

`510.225 Mm^(2) ((10^(7) dm)^(2))/(1 Mm^(2))=5.1022(10)^(16) dm^(2)`