Explanation:
7. density₁ (ρ₁ ) = m₁ /V₁ = 45/15 = 3 g/cm³.
density₂ (ρ₂ ) = m₂ /V₂ = 60/30 = 2g/cm³.
the rock 1 is more dense than rock 2.
rock 2 is less dense.
8. density of lava = mass of lava / volume of lava
= 400/100 = 4g/mL (1mL = 1cm³) = 4g/cm³.
the above rocks will float over lava.
Hope this helps you.
