What is the wavenumber of a radiation having a wavelength of $0.25 \mu m$?

Assertion : All photons possess the same amount of energy.
Reason : Energy of photon does not depend upon wavelength of light used.

Given below are two statements about $X$-ray spectra of elements :
Statement $(I) :$ $A$ plot of $\sqrt{\nu}$ ($\nu =$ frequency of $X$-rays emitted) vs atomic mass is a straight line.
Statement $(II) :$ $A$ plot of $\nu$ ($\nu =$ frequency of $X$-rays emitted) vs atomic number is a straight line.
In the light of the above statements choose the correct answer from the options given below :

Which characteristics of electromagnetic radiation can be explained by its wave nature and particle nature,respectively?

Which of the following is $NOT$ a property of $X$-rays?

$A$ metal surface emits photoelectrons when the incident radiation possesses a minimum.....