A 10 kg cart is pulled by a force of 12 newtons for a distance of 7 meters, then by a force of 4 Newtons for 2 meters, then it is pushed (slowed down) by a force of 3 Newton for 1 meters. All this occurs on a horizontal surface. A)Initially assuming the surface to be frictionless, what net work is done on the cart as it moved the 10 meters? Work total? i know work total = (.5mvfinall^2)-(.5mvinitial^2) I don't know what to plug in for velocity..im stuck here...cause i got to go to work...help please. B)If the cart starts from rest, what is its speed after it has moved the 10 m? Vf=? Now assume a coefficient of friction µ between cart and surface during the entire distance. c) For what value of μ does the cart just come to a halt after 10 m? µ =?? D) For the value of µ computed in part (c), what is the speed of the cart after it has gone 4 m? v=??