Write down structure of the following compounds:
2-hydroxybutanoic acid

Explanation

To write down the structure of 2-hydroxybutanoic acid, we will follow these steps:

### Step 1: Identify the base structure
The name "butanoic acid" indicates that the compound has a four-carbon chain (butane) and a carboxylic acid functional group (-COOH).

**Hint:** The prefix "but-" refers to a four-carbon chain.

### Step 2: Determine the functional groups
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