Aboy finds an abandoned mine shaft in the woods, and wants to know how deep the hole is. he drops in a stone, and counts 4 seconds before he hears the "plunk" of the stone hitting the bottom of the shaft. approximately how deep is the shaft? (assume a gravitational acceleration of 9.8 m/s2 and no significant air resistance.)

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.