A wire has a resistance R. What will be its resistace if (a) it is double on itself and (b) it is stretched so that (i) its length is double and (ii) its radius is halved.

Explanation

To solve the problem, we will analyze the resistance of the wire under two different scenarios: when it is doubled on itself and when it is stretched with specific changes to its length and radius.

### Step-by-Step Solution

**Given:**
- Original resistance of the wire, \( R \)
- Original length of the wire, \( L \)
- Original cross-sectional area of the wire, \( A \)
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