The picture shows Gerald's toy truck, which he can fill with weights, and the track it will travel on.
Gerald puts a weight in the truck and releases it from the starting position, at a height of 0.30 meters. He does this again for each of the weights, releasing the truck from the same position each time. He makes the chart below to keep track of each test.
Which of the following graphs BEST shows the relationship between the potential energy (in joules) of the truck at its starting position and the total mass (in kilograms) of the weighted truck?
A.