HELP!!!Energy problem 1. The problem statement, all variables and given/known data A 20kg object is acted on by a conservative force given by F=-3.0x-5.0x^2, with F in newtons and x in meters. take the potential energy associated with the force to zero when the object is at x=0 a) what is the potential energy of the system associated with the force when the object is at x=2.0m? b)If the object has a velocity of 4.0m/s in the negative direction of the x axis when it is at x=5.0m, what is its speed when it passes through the origin? c)What are the answers to a) and b) if the potential energy of the system is taken to be -8.0J when the object is at x=0. 3. The attempt at a solution a)I can get the equation for finding out PE by integrating F=-3.0x-5.0x^2, which is -1.5x^2-5/3x^3 sub 2.0 into x then the answer I got is -19.3 b) I don't really know how to approach this question, but I know that I have to somehow relate the conservative energy to speed...maybe to kinetic energy???1/2mv^2??? c) a. -8=-1.5x^2-5/3x^3 x=-2.04m but the question says when x=0, so I don't know what did i do wrong with this question b. I didn't know how to do b), so I don't really know how to det the answer for this too. I need some help on this. Thank you very much.