Answer:
Pulley: blinds, garage doors, flag poles.
Lever: see saw, pry bar, lever action door latches.
Wedge: scissors, screw, a knife.
Wheel and axle: office chairs, carts, wheeled carry-on luggage and toy cars.
Inclined Plane: stairs
I think you're asking what his 'ke' will be. Does that mean his 'kinetic energy' ? Well, that'll just be
<em>ke = (1/2) x (his mass) x (his speed when he touches down)²</em>
Answer:
5 billion years ago...ends 4.9 billion years later