Mention the exact location of the Eustachian tube.

Explanation

### Step-by-Step Solution:

1. **Identify the Structure**: The Eustachian tube is a tube-like structure in the human body.

2. **Determine the Function**: It plays a crucial role in equalizing air pressure in the middle ear.

3. **Locate the Eustachian Tube**: The Eustachian tube is located in the middle ear.

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