There must be equal amounts of mass on both side of the center of mass of an object. true or false

False but if we see the distribution of mass on earth crust.

Explanation:

When we take earth crust in the view it is not necessary to have equal amount of masses on the both sides of the earth crust. We can see ocean which are made up of basaltic rocks(heavier) are not evenly distributed. Ocean and continental plates are made up of different types of material and oceanic floor is heavier than continental floor(made up of granitic rocks).

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures