Fill a flat tray with soft, damp sand and stand on the sand. How deep is the imprint that you make in the sand? Now put a block of wood on the sand and stand on the block and measure how far it sinks in. Explain your answer in both the cases.

d is the answer i came up with

truck y has a greater velocity than truck x.

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.