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**A rock thrown....**

A rock is tossed straight up with a speed of 20m/s. When it returns, it falls into a hole 10m deep.

A)What is the rock's velocity as it hits the bottom of the hole?

So I drew the diagram and labelled it as I was taught to do, and then Googled the question to maybe see if I could get a pointer on how it works. The answer I saw that best fit the question was saying that the initial velocity is 0 m/s and that the final velocity is 20 m/s. I understand I need to use the kinematic equations to solve it. But if the question is asking what the final velocity is, why would I assume that the final velocity is 20 m/s? I would assume that the initial velocity is 20 m/s.

Or would I assume that like they said, that the initial velocity is 0 m/s and the final velocity is 20m/s only to find time with a=ΔV/ΔT, using standard acceleration as -9.7m/s

^{2}, and then go from there? I guess I'm just not understanding how we can have a "final velocity" if the question is asking for final velocity.