You release a block from the top of a long, slippery inclined plane of length l that makes an angle θ with the horizontal. the magnitude of the block's acceleration is gsin(θ).1- for an x axis pointing down the incline and having its origin at the release position, derive an expression for the potential energy of the block-earth system as a function of x. suppose that the gravitational potential energy is measured relative to the ground at the bottom of the incline, ug(x=l)=0.express your answer in terms of g and the variables m, l, x, and θ.(u^g=? )2-use the expression you derived in the previous part to determine the speed of the block at the bottom of the incline. (vx, f=? )express your answer in terms of g and the variables m, l, and θ.