Newton's law of gravitation is universal because

Explanation

**Step-by-Step Solution:**

1. **Understanding Newton's Law of Gravitation**:
Newton's law of gravitation states that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

2. **Mathematical Representation**:
The law can be expressed mathematically as:
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