An inventor claims to have constructed an engine that has an efficiency of 75% when operated between the boiling and freezing points of water. Is this possible?

Explanation

To determine whether the inventor's claim of constructing an engine with 75% efficiency between the boiling and freezing points of water is possible, we can use the principles of thermodynamics, specifically the Carnot efficiency.

### Step-by-Step Solution:

1. **Identify the Temperatures**:
- The boiling point of water is 100°C, which is equivalent to 373 K (Kelvin).
- The freezing point of water is 0°C, which is equivalent to 273 K (Kelvin).

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