Which element has `K_(alpha)` x-ray line whose wavelength is 0.180 nm?

Explanation

To find the element that has a K-alpha X-ray line with a wavelength of 0.180 nm, we can follow these steps:

### Step 1: Convert the wavelength to meters
Given the wavelength \( \lambda = 0.180 \, \text{nm} \):
\[ \lambda = 0.180 \times 10^{-9} \, \text{m} \]

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