Name two constituents of biogas.

Explanation

To answer the question about the constituents of biogas, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Biogas**: Biogas is a renewable source of energy produced through the anaerobic breakdown of organic materials. This process occurs in the absence of oxygen and involves the decomposition of organic waste.

2. **Identifying Organic Materials**: The organic materials that can be used to produce biogas include kitchen food waste, animal manure, and agricultural waste. These materials are collected and placed in a biogas plant.

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