Asmall object with mass m = 0.0900 kg moves along the +x-axis. the only force on the object is a conservative force that has the potential-energy function u(x)=−αx2+βx3, where α=2.00j/m2 and β=0.300j/m3. the object is released from rest at small x. when the object is at x = 4.00 m, what are its (a) speed and (b) acceleration (magnitude and direction)? (c) what is the maximum value of x reached by the object during its motion?