Question

What is the mass of a moon rock that occupies 250 mL and has a density of 1.02 g/mL?

Answer 1

Density = mass / volume

Given Data
Density = 1.02 g/mL
Volume = 250 mL
Mass = ?

Plug in the given data
1.02 = m / 250

Cross multiply to get 255 g of moon rock.