Why is the charge on a charged sphere distributed uniformly over its surface?

Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is

Aplane flying horizontally at an altitude of 1 mile and a speed of of 500mih passes directly over a radar station. find the rate at which the distance from the plane to the station is increasing when it is 2mi away from the station.

Which of these is constant for all types of electromagnetic radiation in a vacuum? select one: a. wavelength b. frequency c. photon energy d. amplitude e. velocity