The combined weight of four identical steel blocks is $120\,\text{N}$. Take the gravitational field strength $g$ as $10\,\text{N kg}^{-1}$. What is the mass of a single steel block?
- A$3.0\,\text{kg}$
- B$12\,\text{kg}$
- C$30\,\text{kg}$
- D$48\,\text{kg}$