9514 1404 393
Answer:
118 cm^3
Explanation:
As the units analysis tells you, density is the ratio of mass to volume.
ρ = m/V
V = m/ρ = (304 g)/(2.57 g/cm^3) ≈ 118 cm^3
The volume of the rock is about 118 cm^3.
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There are 1000 g in 1 kg, so 0.304 kg = 304 g.