This passage will test your knowledge on acceleration.

Problem

Researchers are trying to develop ways to reduce the frequency of concussions among professional sports athletes by producing helmet padding that better protect the athletes from direct hits to the head. One way to accomplish this is to try and decrease the magnitude of the acceleration of the struck athlete’s brain.
To test the effect that different padding materials have on the acceleration of a human brain, the researchers used a “dummy” head with ballistic gel “dummy” brain with motion sensors embedded within it. They put the “dummy” head inside the helmets and struck the helmets with a blow from a spring-fired piston. During the collision the researchers monitored the speed of the “dummy” brain as a function of time. A working assumption that the researchers are using is that the worst concussions are caused by the largest instantaneous value (i.e. value at a particular moment in time) of the acceleration of the brain.
The data collected in the experiment is shown below.
Figure 1. The velocity vs time graph of the dummy brain. Each line represents different padding used by the researchers.
Describe the acceleration experienced by the “dummy” brain during the 5 millisecond interval when using padding D.
Please choose from one of the following options.