Step-by-step explanation:
[tex]density = \frac{mass}{volume} \\ volume = \frac{mass}{density} \\ changing \: 1.8 {gcm}^{ - 3} to \: {kgm}^{ - 3} \\ multiply \: by \: 1000 \\ = 1800 {kgm}^{ - 3} \\ volume = \frac{3.1}{1800} \\ = 0.00172 {m}^{ 3} [/tex]