Why does river water contain lot of impurities?

Explanation

### Step-by-Step Solution:

1. **Understanding the Source of River Water**:
- River water originates from various sources such as mountains, glaciers, and rainfall. As it flows, it travels through different terrains.

2. **Long Journey of River Water**:
- Rivers often have long courses, flowing over land surfaces from high altitudes to lower areas. During this journey, the water interacts with the environment.

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