give examples of materials whose electrical resistivity decreases with increases in temperature.

Explanation

To answer the question about materials whose electrical resistivity decreases with an increase in temperature, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Resistivity and Temperature Relationship**:
- Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. For most conductors, resistivity increases with temperature due to increased collisions between electrons and atoms.
- However, in certain materials, particularly semiconductors and insulators, resistivity can decrease with an increase in temperature.

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