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Person A is traveling by car 45 m/s relative to the ground. Person A then sees Person B approach them and travel alongside them for a few seconds(we'll call it event 1). Person A then sees Person B accelerate for 10 seconds, and a speedometer records Person B's velocity to be 100 m/s (we'll call it event 2). What is Person B's velocity relative to Person A in event 1? In event 2? Relative to Person B, what is Person A's acceleration?
What is v1 = 0 m/s, v2 = 55 m/s, a(A/B) = -5.5 m/s^2