A group of researchers investigated the effects of two vocabulary learning strategies on word retention two weeks later. In this example, learning strategy is the variable and word retention is the
variable.

While standing outdoors one evening, you are exposed to the following four types of electromagnetic radiation: yellow light from a sodium street lamp, radio waves from an am radio station, radio waves from an fm radio station, and microwaves from an antenna of a communications system. rank these type of waves in terms of increasing photon energy.