The diagram below shows the path of a soccer ball as it travels from start to finish. The arrow represents a force acting on the ball. Which force is represented by the arrow?

The diagrams $A$ and $B$ below show a student moving the same boxes in two different ways. In diagram $B, the student is using wheels, which are part of a simple machine. It will be easier for the student to use wheels to push the boxes in diagram $B$ because there is