Calculate the wavelength of the emitted characteristic X-ray from a tungsten `(Z = 74)` target when an electrons drops from an `M` shell to a vacancy in the shell.

Explanation

To calculate the wavelength of the emitted characteristic X-ray from a tungsten target when an electron drops from the M shell to a vacancy in the K shell, we can follow these steps:

### Step 1: Identify the Transition
The transition is from the M shell (n=3) to the K shell (n=1). This transition is known as the K-beta line.

### Step 2: Use the Rydberg Formula for X-rays
The wavelength of the emitted X-ray can be calculated using the modified Rydberg formula for X-rays:
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