Can `L_alpha` X-ray of one material have shorter wavelength than `K_alpha` X-ray of another?

Alpha rays are

X-ray incident on a material

Show that the frequency of K_beta X-ray of a material equals the sum of the frequencies of K_alpha and L_alpha X-rays of the same material. (##HCV_VOL2_C44_S01_006_Q01##)

The wavelength of x-rays is of the order of

For characteristic X - ray of some material

X-rays can be used

The cut-off wavelength of an X-ray depends on

The frquencies of K_alpha, K_beta and L_alpha X-rays of a materail are gamma_1, gamma_2 and gamma_3 respectively. Which of the following relation holds good?

Use Moseley's law with b = 1 to find the frequency of the K_alpha X-ray of La(Z = 57) if the frequency of the K_alpha X-ray of Cu(Z = 29) is known to be 1*88 xx 10^(18) Hz.

Use Moseley's law with b = 1 to find the frequency of the K_alpha X-ray of La(Z = 57) if the frequency of the K_alpha X-ray of Cu(Z = 29) is known to be 1*88 xx 10^(18) Hz.