The diagram illustrates a pump known as a hydraulic ram. For one pump of this type, the long approach pipe contains $500\,\text{kg}$ of water. When the speed of this water reaches $2.0\,\text{m s}^{-1}$, a valve closes, and the kinetic energy of the water is then used to raise a small amount of water through a height of $15\,\text{m}$. The pump has an efficiency of $10\%$. What mass of water can be raised $15\,\text{m}$?
- A$0.15\,\text{kg}$
- B$0.68\,\text{kg}$
- C$1.5\,\text{kg}$
- D$6.8\,\text{kg}$