1) which color has the longest wavelength?
a- red
b- blue
c- green
d- orange
2) gamma rays, x-rays, visible light, and radio waves are all types of
a- nuclear energy
b- chromatic aberration
c- ultraviolet radiation
d- electromagnetic radiation
3) the fact that light can exert a pressure on mater suggests that it is made of particles called
a- electrons
b- protons
c- photons
d- neutrons

1-Red color has the longest wavelength. Red light belongs to the visible spectrum of light and the wavelength of visible spectrum ranges from 700nm to 400nm, from red to violet respectively.

2- Gamma rays, x-rays, visible light and radio waves are all types of electromagnetic radiations. Electromagnetic radiations contain visible light, radio waves, gamma rays and x-rays. These radiations has varied electric and magnetic fields.

3- The fact that light can exert a pressure on matter suggests that it is made up of photons.