Write the structures of the monomers used for getting the following polymers:
(a) Polyvinyl chloride (PVC)
(b) Melamine-formaldehyde polymer
(c) Buna-N

Explanation

To solve the question of identifying the monomers used to produce the specified polymers, we will go through each polymer one by one and provide the structure of its corresponding monomer.

### (a) Polyvinyl Chloride (PVC)

**Monomer Structure:**
The monomer used to produce Polyvinyl Chloride is Vinyl Chloride. The structure of Vinyl Chloride can be represented as follows:

\[ \text{CH}_2= \text{CHCl} \]
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