An element of atomic number 9 emits `K_(alpha)` X-ray of wavelength `lamda`. Find the atomic number of the element which emits `K_(alpha)` X-ray of wavelength `4lamda`.

Explanation

To solve the problem, we will use the formula for the wavelength of K-alpha X-rays emitted by an element, which is given by:

\[ \frac{1}{\lambda} = R \cdot (Z - 1)^2 \]

where:
- \(\lambda\) is the wavelength of the K-alpha X-ray,
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