The volume of a $500\, g$ sealed packet is $350\, cm^3$. Will the packet float or sink in water if the density of water is $1\, g\, cm^{-3}$? What will be the mass of the water displaced by this packet?

(N/A) Density of the packet = $\frac{\text{Mass}}{\text{Volume}} = \frac{500\, g}{350\, cm^3} \approx 1.43\, g/cm^3$.
Since the density of the packet $(1.43\, g/cm^3)$ is greater than the density of water $(1\, g/cm^3)$,the packet will sink in water.
According to Archimedes' principle,the volume of water displaced by a fully submerged object is equal to the volume of the object.
Mass of displaced water = $\text{Volume of packet} \times \text{Density of water} = 350\, cm^3 \times 1\, g/cm^3 = 350\, g$.