$11.$ In a vertical jump$-$and$-$reach test, $60$ kg Blake Griffin $($shedding the pounds for those LA

summers.....oops, Detroit summers...wait, Brooklyn, who does he play for now???$)$

jumps $70$ cm$,$ while $90$ kg DeAndre Jordan jumps $55$ cm$.$ Assuming both jumps took the

same amount of time, which jumper was more powerful?

Griffin$412$ J$/$t

Jordan$485$ J$/$t

$12.$ Sterling Archer has given up Lacrosse and taken up pole vaulting. At the end of his

approach run during a pole$-$vault, he has a horizontal velocity of $9$ m$/$s and his center of

gravity is $1\mathrm{.}5$ m high. If Archer has a mass of $60$ kg$,$ estimate how high he should be able

to vault if his kinetic and potential energies are all converted to potential energy.

$5\mathrm{.}63$ m