Complete the following by suppling intermediates
`C_(6)H_(5)CH_(2)CH_(3) overset(KMnO_(4))underset(KOH, 373 K)(to) A overset(NaOH+ CaO)underset(630K) (to)B`

Explanation

To solve the given question, we will break down the reactions step by step.

### Step 1: Identify the starting compound
The starting compound is C₆H₅CH₂CH₃, which is known as phenethyl alcohol or phenethyl.

### Step 2: First reaction with KMnO₄ and KOH at 373 K
When phenethyl (C₆H₅CH₂CH₃) is treated with KMnO₄ in the presence of KOH at 373 K, it undergoes oxidation. KMnO₄ is a strong oxidizing agent, and under these conditions, the primary alcohol group (-CH₂-) is oxidized to a carboxylic acid (-COOH).

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