The electromagnetic spectrum. Electromagnetic waves, which include light, consist of vibrations of electric and magnetic fields, and they all travel at the speed of light. $($a$)$ FM radio. Find the wave$-$ length of an FM radio station signal broadcasting at a frequency of $108\mathrm{.}0$ MHz$.($b$)$ X rays. X rays have a wavelength of about $0\mathrm{.}18$ nm$.$ What is their frequency? $($c$)$ The Big Bang. Microwaves with a wavelength of $1\mathrm{.}18$ mm$,$ left over from soon after the Big Bang, have been detected. What is their frequency? $($d$)$ Sunburn. Sunburn $($and skin cancer$)$ is caused by ultraviolet light waves having a frequency of around $1\mathrm{.}01*1016$ Hz$.$ What is their wavelength? $($e$)$ SETI. It has been suggested that extraterrestrial civilizations $($if they exist$)$ might try to communicate by using electromagnetic waves having the same frequency as that given off by the spin flip of the electron in hydrogen, which is $1\mathrm{.}48$ GHz$.$ To what wavelength should we tune our telescopes in order to search for such signals? $($f$)$ Microwave ovens. Microwave ovens cook food with electromagnetic waves of