What is the correct order of frequency for $\gamma-$ rays $(b)$,$X-$ rays $(a)$,and $UV-$ rays $(c)$?

If $\lambda_r$,$\lambda_v$,and $\lambda_x$ are the wavelengths of red light,violet light,and $X$-rays respectively,then which of the following relations is correct?

Electromagnetic radiation used to sterilise milk is

Which of the following radiations has the shortest wavelength?

Write the range of ultraviolet waves.

Which rays are not a portion of the electromagnetic spectrum?