Draw structures of the following derivatives.
(i) The ethylene ketal of hexan-3-one
(ii) The methyl hemiacetal of formaldehyde

Explanation

To solve the question, we will draw the structures of the specified derivatives step by step.

### (i) The Ethylene Ketal of Hexan-3-one

**Step 1: Identify Hexan-3-one Structure**
- Hexan-3-one is a ketone with the following structure:
- It has 6 carbon atoms (C1 to C6) and a carbonyl group (C=O) at the third carbon (C3).

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