To have practical applications why are cross links quetioined in rubber?

Explanation

**Step-by-Step Solution:**

1. **Understanding Rubber and Its Properties:**
- Natural rubber is a polymer that exhibits elastomeric properties, meaning it can stretch and return to its original shape. However, it has limitations such as becoming soft at high temperatures and brittle at low temperatures.

2. **Temperature Effects on Rubber:**
- At high temperatures (above 335 K), natural rubber becomes soft, which can lead to deformation under stress.
- At low temperatures (below 213 K), it becomes brittle, making it prone to cracking and breaking.
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