Medusa rollercoaster homework. How to find speed going up and down largest hill?

For a homework project we have to find the speed going up and down the largest hill on the Medusa Rollercoaster in Six Flags Discovery Kingdom.

http://en.wikipedia.org/wiki/Medusa_%28Six_Flags_Discovery_Kingdom%29

Max speed 65 mph
The drop begins at 150 feet.
How do I find out the speed?

Mythical Medusa

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