Write down structure of the following compounds:
3-methylpentanoic acid

Explanation

To draw the structure of 3-methylpentanoic acid, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Base Chain**: The name "pentanoic acid" indicates that the main chain consists of 5 carbon atoms (pentane). The "oic acid" suffix indicates the presence of a carboxylic acid functional group (-COOH) at one end of the carbon chain.

2. **Draw the Carbon Backbone**: Start by drawing a straight chain of 5 carbon atoms. This can be represented as:
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