Item RG174001: Kinetic energy is proportional to mass, so when a moving object has its mass increased by two the kinetic energy of that object increases by two. (Item uses bar graphs.)

Two cars are driving next to each other on the highway as shown below. In Figure 1, both cars are traveling at the same 40 km/hr. In Figure 2, both cars increase their speed to 60 km/hr.

       

If Car B weighs 500kg more than Car A, which of the following graphs shows the levels of kinetic energy (motion energy) of each car in Figures 1 and 2?