A 0.15kg ball is thrown into the air & rises to a height of 20m. How much kinetic energy did the ball initially have?

and

A 125g steel ball with a kinetic energy of .25J rolls along a horizontal track. How long will the call roll if friction can be ignored?

Please, please, please help.

I've already done 67 pages of work and I just don't know a couple of the answers.

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