Complete the following sequence of reactions with appropriate structures.
`CH_(3) -CH_(2) -COOH overset(P and ) underset("Bromide") rarr (A)`
`(A) overset((i) Alc. KOH (excess)) underset((ii) H^(oplus))rarr (B)`.

Explanation

To solve the given sequence of reactions, we will follow the steps outlined in the video transcript and provide the appropriate structures at each stage.

### Step 1: Reaction of Propanoic Acid with Phosphorus and Bromide
1. **Starting Material**: Propanoic acid (CH₃-CH₂-COOH).
2. **Reagents**: Phosphorus (P) and Bromide (Br₂).
3. **Reaction Type**: This is a halogenation reaction that occurs at the alpha position of the carboxylic acid. The presence of phosphorus facilitates the bromination of the alpha carbon (the carbon adjacent to the carboxylic acid).
4. **Product**: The product formed is 2-bromopropanoic acid (CH₃-CH(Br)-COOH).

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