The diagrams display a rectangular box in its empty state and the same box after being filled with liquid. The mass of the empty box is $60\ \text{g}$. Once the liquid is added, the combined mass of the box and the liquid is $300\ \text{g}$. The liquid has a density of $1.2\ \text{g cm}^{-3}$. Determine the volume of the liquid in the box.
- A$50\ \text{cm}^3$
- B$200\ \text{cm}^3$
- C$250\ \text{cm}^3$
- D$300\ \text{cm}^3$