Write down structure of the following compounds:
3-methyl-2-butenoic acid

Explanation

To draw the structure of 3-methyl-2-butenoic acid, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Base Chain**: The name "butenoic acid" indicates that the base chain has 4 carbon atoms (but-). The "enoic" part indicates that there is a double bond in the chain.

2. **Determine the Position of the Double Bond**: The "2-" in "2-butenoic acid" tells us that the double bond is located between the second and third carbon atoms.

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