Respuesta :

they travel the speed of light or 300,000 km per second

AL2006

Radio, infrared, ultraviolet, X-rays, gamma Ray's, and light that you can see, are all electromagnetic waves, and all travel at the "speed of light".

Exactly: 299,792,458 meters per second, in vacuum

Easier to remember: 300,000 kilometers per second, in vacuum

Slower in any material stuff. Depends on the substances.