Answer
See explanation
Work Step by Step
a. Based on the observations, it seems that the internal mechanism of the box is likely a system of pulleys and ropes. Rope B is likely not connected to the other ropes, allowing it to move freely. Rope A is connected to rope C, and when rope A is pulled, it causes rope C to be pulled slightly into the box. Similarly, when rope C is pulled, it causes rope A to almost disappear into the box.
b. To refine the model, further experiments that could be done include:
Pulling on rope A and rope C simultaneously to determine the relative tension on the ropes and the direction of movement of the ropes.
Observing the movement of the ropes when pulling on rope A and C at different strengths and observing the behavior of the ropes.
Attempting to move the box, to see if the ropes move with the box or stay in place.
Measuring the length of the ropes and the distance between the pulleys and the box.
Opening the box and inspecting the internal mechanism, if possible.
