What principle states about the fundamental limitation that, for a particle as small as the electron, one cannot know exactly where it is and at the same time know its energy how it is moving?

A. Answer the following questions:

1. Who proposed the theory that electrons in an atom orbit in well-defined orbits around the nucleus?

2. The phenomenon when electrons are ejected from a metal surface if light of a high enough frequency hits the surface of the metal.

3. Why does hydrogen form a line spectrum rather than a continuous spectrum (you can actually answer this question by writing only three words)?

4. There is a fundamental limitation to just how precisely we can know both the position and momentum of a particle at a given time. This principle is named after which scientist?