Hydrogen is _____ (`"combustible"//"non-combustible"`)

Explanation

To determine whether hydrogen is combustible or non-combustible, we can follow these steps:

### Step-by-Step Solution:

1. **Define Combustible and Non-Combustible:**
- A **combustible substance** is one that can burn in the presence of air, producing heat and light.
- A **non-combustible substance** is one that does not burn in air and does not produce heat and light.

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