Any four Properties
i. They are electromagnetic waves of very short wavelength
ii. They travel with speed of light.
iii. They affect photographic plates.
iv. They produce fluorescence in many substances.
v. They can be reflected or refracted under certain conditions.
vi. They are not deflected by magnetic or electric field.
vii. They have high penetrating power.
viii. They produce photoelectric effect.
ix. They are invisible to eyes.
x. X-ray kill some form of animal cell