A crane is being used to raise containers from a ship. One container has a mass of $14\,000\,\text{kg}$ and is lifted straight up at a speed of $3.2\,\text{m s}^{-1}$. The electric motor providing the power to lift the container draws a current of $240\,\text{A}$ with a potential difference of $2200\,\text{V}$. What is the efficiency of the system?
- A$8.1\%$
- B$8.5\%$
- C$48\%$
- D$83\%$