Topic: Kinematics
Concepts: Motion graphs

Solution:

On a velocity-time graph, the displacement is given by the area under the curve.

Thus, the maximum displacement occurs when the velocity goes to zero (at $t=2.5\,\mathrm{s}$). From the graph, we have $\Delta x=7\,\mathrm{m}$ so the answer is D.

Topic: Kinematics
Concepts: Motion graphs

Solution:

Since the acceleration is given by the slope of a velocity-time graph, we see the car travels at three different accelerations from beginning to end. From the graph, the car has a small positive acceleration for part I of the motion, zero acceleration for part II, and a large negative acceleration for part III. Thus, the answer is C.