Answer:
a) Dark energy is the cause of the acceleration of the universe, while dark matter is the cause of the formation of structures.
e) There is much more dark energy in the universe, by mass.
Explanation:
Dark energy rises as an explanation of the accelerated expansion of the Universe, since it was expected that this slow down since The Big Bang, as a consequence of the gravitational attraction between the different objects (galaxies, planets, etc) but instead, the observations show how it is accelerating.
Dark matter in the other hand was born to explain why stars that were more farther for the supermassive black hole in the center of the Milky way galaxy didn't decrease their rotational velocity as it was expected.
[tex]v = \sqrt{\frac{G M}{r}}[/tex]
Where v is the rotational velocity, G is the gravitational constant, M is the mass inside the orbital radius, and r is the orbital radius.
If the distance increases the orbital speed decreases (inversely proportional).
