Describe the motion of the box: A)The box will not move because the forces acting on the box are balanced.
B)The box will move 75N to the right, because the forces are unbalanced.
C)The box will move 75N to the left, because the forces are unbalanced.

tube or goog will be great resources to find the answer to the question that you're asking

reserve is the answer

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.