A single conservative force F(x) acts on a 1.6 kg particle that moves along an x axis. The potential energy U(x) associated with F(x) is given by

U(x) = -2.9xe-x/3
where x is in meters. At x = 3.4 m the particle has a kinetic energy of 7.2 J. (a) What is the mechanical energy of the system? (b) What is the maximum kinetic energy of the particle and (c) the value of x at which it occurs?