Reaction and braking contribute different distances - Online practice 2

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Educational model only: speed v=15 m/s stays constant for reaction time 0.8 s, then braking has constant deceleration magnitude a=5 m/s^2 to rest. Thinking distance=vt; braking distance=v^2/(2a). Ignore other changes only for this supplied model. Do not test this on a road or treat it as a safe-distance guarantee.