A student is positioned $180\,\text{m}$ away from a vertical, flat cliff and strikes two pieces of wood together to produce a brief, loud sound. A timer shows that the echo is heard $1.5$ seconds after the wood is struck together. Using this information, what is the speed of sound?
- A$120\,\text{m s}^{-1}$
- B$240\,\text{m s}^{-1}$
- C$270\,\text{m s}^{-1}$
- D$540\,\text{m s}^{-1}$