A small rock is thrown vertically upward with a speed of 16.0 m/s from the edge of the roof of a 23.0 m tall building. T

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A small rock is thrown vertically upward with a speed of
16.0 m/s from the edge of the roof of a
23.0 m tall building. The rock doesn't hit the building
on its way back down and lands in the street below. Air resistance
can be neglected.
A. What is the speed of the rock just before it hits the
street?
Express your answer with the appropriate units.
B. How much time elapses from when the rock is thrown until it
hits the street?
Express your answer with the appropriate units.