According to Kepler's model of the solar system, what is retrograde motion is caused by? Select one: a. epicycles. b. the daily turning of the celestial sphere. c. the difference in orbital speed of Earth and other planets. d. the changing speed of the Sun. e. the Earth's rotation.

Amight be the answer

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By water evaporation from the leaves is created a negative pressure at the top of the tree that promotes the ascension  of the water through channels that are called xylem. there are also two molecule forces that are involved: the intra-water molecules cohesion (water molecules stick to each other) and the adhesion when the water molecules stick to the channels they are running in. this is what enables water to go from the roots to the top of a tall tree.