The Graph in the Figure Shows the X Component of the Acceleration

Short Answer

The graph in the figure shows the x component of the acceleration of a 2.4-kg object as a function of time (in ms).
(a) At what time(s) does the x component of the net force on the object reach its maximum magnitude, and what is that maximum magnitude?
(b) What is the x component of the net force on the object at time t = 0.0 ms and at t = 4.0 ms?