(a) A person can see clearly upto `80 cm`. He uses spectacles of `-0.80 dioptre`, how far can he see clearly ?
(b) If a person uses spectacles of power `+ 1.0 dioptre`, what is the nearest distance of distinct vision for him ? Given that near point of the person is `75 cm` from the eye.

Explanation

To solve the given problem, we will break it down into two parts as specified in the question.

### Part (a):
A person can see clearly up to 80 cm and uses spectacles of -0.80 dioptre. We need to find out how far he can see clearly with these spectacles.

1. **Calculate the Focal Length of the Lens**:
The power (P) of the lens is given as -0.80 dioptre.
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