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Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.

Select all the correct answers. which three statements about electromagnetic radiation are true?

An electron is ejected into a horizontal uniform e⃗ field at a parallel horizontal velocity of v0. assume the electron's initial position x0, initial velocity v0, time t, magnitude of electric field e, electron's mass m, and the magnitude of the electron's charge |e|. ignore the force that earth exerts on the electron. assume the e⃗ field is in the same direction as the initial velocity. part a define the equation for the electron's velocity. express your answer in terms of the variables v0, |e|, t, e, and m.