The lens mentioned in 6 (b) above is of focal length 25 cm. Calculate the power of the lens.

Explanation

To calculate the power of a lens given its focal length, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Focal Length**:
The focal length (F) of the lens is given as 25 cm.

2. **Convert Focal Length to Meters**:
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