The input and output for a transformer are given below. Input: potential difference $11000\,\text{V}$, current $28\,\text{A}$. Output: potential difference $240\,\text{V}$, current $1200\,\text{A}$. Determine the efficiency of the transformer.
- A$0.94\,\%$
- B$1.0\,\%$
- C$11\,\%$
- D$94\,\%$