(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

"Estimate the mass of water in all the World’s oceans."

2. Relevant equations

I know the following:

Two-thirds of the earth is sea.

The density of seawater is 1025 kg/m^{3}.

Radius of the earth = 6.3*10^{6}m.

3. The attempt at a solution

Let's assume that the earth's crust is a spherical shell that has a thickness of 0.001 times the radius of the earth.

So, the volume of the crust = (4[tex]\pi[/tex]r^{2})(r_{outer}-r_{inner}) = 3.1*10^{18}m^{3}.

So, volume of seawater = 2.1*10^{18}m^{3}.

So, mass of seawater = 2.1*10^{21}kg.

Is the answer reasonable? How might I improve it?

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# Homework Help: Numerical Estimation problem

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