A teacher uses several marbles in a flat rectangular container to illustrate concepts of thermodynamics. The marbles in the container serve as a model for the molecules in an ideal gas. The teacher presents the class with two different situations.
In Situation A, all the marbles are traveling from left to right across the container at the same speed.
In Situation B, the marbles have the same average speed, but they all move in different directions.
Which statement below correctly uses these situations to illustrate a thermodynamic concept?