The sound of an explosion on the surface of a lake is heard by a boatman 100 m away and by a diver 100 m below the point of explosion.
If sound takes time `t` s to reach the boatman, how much time (approximately) will it take to reach the diver?

Explanation

To solve the problem, we need to determine the time it takes for sound to reach the diver, who is located 100 meters below the explosion point, in relation to the time it takes for the sound to reach the boatman, who is 100 meters away horizontally.

### Step-by-Step Solution:

1. **Identify the Distances**:
- The boatman is 100 meters away horizontally from the explosion.
- The diver is 100 meters below the explosion.

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