Which is a better fuel, biogas or wood? Give reasons to support your answer.

Explanation

To determine whether biogas or wood is a better fuel, we will analyze both fuels based on their sources, combustion characteristics, environmental impact, and calorific value.

### Step-by-Step Solution:

1. **Source of Fuel**:
- **Biogas**: Biogas is produced from the decomposition of organic matter, specifically from plant and animal waste. This process occurs in anaerobic conditions (absence of oxygen).
- **Wood**: Wood is obtained by cutting down trees. It is a natural resource that requires deforestation for its procurement.

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