Since the color is oranfe and we need to find frequency the first thing that we should do is to divide the speed of light by [tex]2.998 * 10**8[/tex] m per sec. of wavelength which was given in that way [tex]6.2 * 10**-7[/tex]. The next thing you should do is do the division and in a result you will have [tex]4.835 * 10**14 cycles per second[/tex]