The figure indicates the energy level diagram of an atom and the origin of six spectral lines in emission (e.g. line no. $5$ arises from the transition from level $B$ to $A$). The following spectral lines will also occur in the absorption spectrum

The figure represents the observed intensity of $\mathrm{X}$-rays emitted by an $\mathrm{X}$-ray tube as a function of wavelength. The sharp peaks $A$ and $B$ denote

If the potential difference between the anode and the cathode of the $\mathrm{X}$-ray tube increases 

In the diagram, a graph between the intensity of $X$-rays emitted by a molybdenum target and the wavelength is shown, when electrons of $30 \mathrm{keV}$ are incident on the target. In the graph, one peak is of $K_{\alpha }$ line and the other peak is of $K_{\beta }$ line.

Let ${\lambda }_{\alpha }, {\lambda }_{\beta }$ and ${\lambda }_{\alpha }^{\text{'}}$ denote the wavelengths of the $X$-rays of the $K_{\alpha }, K_{\beta }$ and $L_{\alpha }$ lines in the characteristic $X$-rays for a metal