An arrow is launched straight up with a velocity of 15.0 m/s. How long before the arrow returned to the ground?

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.

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This is the substance(s) formed in a chemical reaction.