Water should not be used to put off electrical fires or burning oil and petrol. Instead sand or soil should be used. Why?

Explanation

### Step-by-Step Solution:

1. **Understanding Electrical Fires**:
- Water is a good conductor of electricity. When water is used to extinguish an electrical fire, it can conduct electricity and pose a risk of electric shock to the person trying to put out the fire. Therefore, water should not be used for electrical fires.

2. **Understanding Oil and Petrol Fires**:
- Water is denser than oil and petrol. When water is poured on burning oil or petrol, it sinks to the bottom because it is heavier. As a result, the oil or petrol continues to float on top and burns, making the fire worse instead of extinguishing it.

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