How far can tectonic plates move in a year? 0 centimeters 15 centimeters 20 centimeters 30 centimeters

On average, the mid-Atlantic tectonic plates move 2.5 cm per year. The Pacific plates are moving at an average speed of 7-11 cm per year. Given this information, we can conclude that tectonic plates do shift every year rendering the answer, 0 centimeters, as incorrect. By comparing the mid-Atlantic and Pacific plates together, we can assume that they are not moving much every year. Therefore the answer to your question is 15 centimeters. 

Deduce law of conservation of momentum from Newton's third law of motion. Consider two bodies A and B of masses mA and mB moving in the same direction along a straight line. ... Thus, total momentum of the two bodies is conserved provided no external force acts on them. This proves the law of conservation of momentum.

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