A convex lens has focal length 20 cm. What is the power of the lens?

Explanation

To find the power of a convex lens with a focal length of 20 cm, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Focal Length**:
The focal length (f) of the lens is given as 20 cm.

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