Identify the physical and chemical changes among the following.
(a) Preparation of liquefied petroleum gas
(b) Usage of liquefied petroleum gas
(c ) Formation of manure
(d) Formation of glass
(e) Breaking of glass

Explanation

To identify the physical and chemical changes among the given options, we will analyze each one based on the definitions of physical and chemical changes.

### Step-by-Step Solution:

1. **Preparation of liquefied petroleum gas (LPG)**:
- This process involves the decomposition of organic matter (plants and animals) over millions of years under high pressure and temperature. It results in the formation of new substances (hydrocarbons).
- **Type of Change**: **Chemical Change** (new substances are formed).

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