General Chemistry-Level 4

First take a look at the properties of Graphene.
1) 200 times stronger than steel.
2) Thinnest material on earth.( 1 million times thinner than hair)
3) Worlds most conductive material
source-"http://www.graphene.manchester.ac.uk/#/explore/the-top-graphene-facts/"
The first piece of information required to solve this puzzle is the surface area of the earth. (Google it)
$S=5.10 \times 10^8km^2$
The next value required to solve the puzzle is the mass per unit area of graphene.
$G=0.76mg/m^2$ There is simple derivation to calculate above,very interesting and elementary. Imgur