<span>Taking into account the information above, we know the average mass of the bucket of water may be m=20-5/2=17.5kg. As the bucket of water is pulled at a "constant velocity" the work required to raise the bucket to the platform transformed into the potential energy of the bucket of water. That is why it should be W=mgh=17.5*9.8*40=6860J</span>
Well, it goes 60 miles in one hour......so set up a ratio.....
60 miles/5 miles = 1 hr/x.....you'll get 60x = 5....then 5/60 would be 0.083
So the heavy skateboarder will move off with speed 2.45 m/s in the opposite direction
D
Its D i think because it doesnt refer to any other things
