Question

How many dry sand grains are on Earth's beaches?

Guess that the length of Earth's beaches is about twice the Earth's circumference.

Guess that a sand grain has a radius of about 0.5 millimeter. *** PLEASE ANSWER 6 QUESTIONS BELOW**

All numbers must be entered as, say, 5000 or 5e3 or 5.0e3 and not with commas as in "5,000" and not as fractions as in "3/4" and not> as percentages as in "70%".  

1 Estimate the volume of one dry sand grain (in meter³, see Hint). ????

2 Estimate the width (in meters) of a typical beach. ???

3 Estimate the depth (in meters) of a typical beach.

4 Estimate the total length (in meters) Earth's beaches (see Description).

5 Estimate the volume (in meter³) of Earth's beaches.

6 Estimate the number of dry sand grains on Earth's beaches.

Answer 1