What is the volume in ml of a 1.11 carat diamond, given the density of diamond is 3.51 g/ml? (1 carat = 200 mg). use significant figures

We will have to have first in mind the formula of density:
ρ , where ρ is the density, m is the mass and V is the volume. 
We will next calculate the mass of the diamond:
1 carat ............................................... 200 mg
1.1 carat ............................................ x mg.
 
We will next find out the volume:
ρ => V = = 

Mgo2 is the oxidation state of manganese oxide