Answer:
The opponent-process theory
Explanation:
The opponent process theory is based on the human visual system and according to the theory the interpretation of the color is done by the photo-receptors rods and cones in the human eye.
This theory states that the perception of color is governed by the two opponent system which includes - a red-green, a blue-yellow and a black-white mechanism.
Any activity in one of these restricts the activity in the other.
Answer:
(a) 
(b) 
Explanation:
(a) We use Newton's law of universal gravitation, in order to calculate the gravitational force between electron and proton:
Where G is the Cavendish gravitational constant, 
and 
are the masses of the electron and the proton respectively and r is the distance between them:
The minus sing indicates that the force is repulsive. Thus, its magnitude is:
(b) We use Coulomb's law, in order to calculate the electric force between electron and proton, here k is the Coulomb constant and e is the elementary charge:
Its magnitude is:
C :) cause a direction has nothing do do with velocity !
Explanation:
when a main-sequence star exhausts its core hydrogen fuel supply the core starts to shrink ( lack of fusion reactions) and the rest of the star starts to expands. The fusion reaction leaves the main sequence and begin to fuse helium in a shell outside the core. This mass stars become red supergiant and then evolve to become blue super giant.
