Altitude of 575m with zero initial velocity; 8.0s she falls freely; rate of descent et 15m/s^2 until her rate of descent reaches 5.0m/s.At this point she adjust her rocket engine control to maintain that her rate of descent until she reaches ground.

How much time is required for the entire trip from the helicopter to the ground?
what is her average velocity for the entire trip?

danny or monica or whoever,

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Thanks.