When a person's clothes catch fire, you should quickly wrap him in a thick blanket and roll him on the ground. Why?

Explanation

**Step-by-Step Solution:**

1. **Understanding Fire and Combustion**: Fire requires three elements to sustain itself: fuel, heat, and oxygen. This is known as the fire triangle. In the case of a person whose clothes are on fire, the clothes serve as the fuel, and the oxygen in the air supports the combustion.

2. **Immediate Action**: When a person's clothes catch fire, the immediate action is crucial. Wrapping the person in a thick blanket is one of the most effective first aid responses.

3. **Covering with a Blanket**: By covering the person with a thick blanket, you effectively smother the flames. The blanket acts as a barrier between the fire and the oxygen in the air.

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