Find the power of a concave lens of focal length `2 m`.

Explanation

To find the power of a concave lens with a focal length of \(2 \, \text{m}\), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Focal Length**:
- The focal length of a concave lens is considered negative in the Cartesian coordinate system. Given that the focal length \(f\) is \(2 \, \text{m}\), we represent it as:
\[
f = -2 \, \text{m}
...