Write down the structures of close homologues of heptane having one quaternary `C` atom in their molecule and the other having two tertiary carbon atoms.

Explanation

To solve the question, we need to identify the structures of close homologues of heptane that contain one quaternary carbon atom in one structure and two tertiary carbon atoms in another structure.

### Step-by-step Solution:

1. **Identify the Homologues of Heptane:**
- Heptane (C7H16) is a straight-chain alkane with 7 carbon atoms. The homologues of heptane differ by the addition or removal of a CH2 group.
- The close homologues of heptane are hexane (C6H14) and octane (C8H18).

...