Draw the structures of the following compounds:
3-methyl-2-oxobutanoic acid.

Explanation

To draw the structure of 3-methyl-2-oxobutanoic acid, follow these steps:

### Step 1: Identify the Parent Chain
The name "butanoic acid" indicates that the parent chain consists of four carbon atoms (butane). The "acid" part indicates that there is a carboxylic acid functional group (-COOH) at one end of the chain.

### Step 2: Draw the Carbon Backbone
Draw a straight chain of four carbon atoms. This can be represented as:
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