Three essential requirements for producing fire are fuel, heat and ________

Explanation

To answer the question regarding the three essential requirements for producing fire, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Requirements**: Fire requires three essential components to ignite and sustain itself. These components are commonly known as the fire triangle.

2. **First Component - Fuel**: The first requirement is **fuel**. Fuel is any material that can combust, such as wood, paper, gasoline, or any other combustible substance.

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