A ship at rest on the sea surface sends sound pulses straight down to the sea bed. Each pulse that is reflected by the sea bed is detected after $1.0\,\text{ s}$ has elapsed since it was transmitted. When a whale passes beneath the boat, the received pulse arrives after $0.60\,\text{ s}$. The speed of sound in sea water is $1500\,\text{m s}^{-1}$. How far above the sea bed is the whale?
- A$300\,\text{m}$
- B$450\,\text{m}$
- C$600\,\text{m}$
- D$750\,\text{m}$