What do you mean by range of vision ?

Explanation

### Step-by-Step Solution:

1. **Definition of Range of Vision**: The range of vision refers to the distance over which the human eye can see objects clearly. It is defined by two specific points: the near point and the far point.

2. **Near Point**: The near point is the closest distance at which the eye can see objects clearly. For a normal human eye, this distance is typically around 25 centimeters. Objects closer than this distance appear blurry.

3. **Far Point**: The far point is the farthest distance at which the eye can see objects clearly. For a normal eye without any defects, this distance can be considered to be practically infinite. This means that a healthy eye can see distant objects clearly without any difficulty.

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