What is the primary reason an object at rest begins to move?

The object's mass suddenly decreases.

All forces acting on it become balanced.

An unbalanced force is applied to it.

Gravity stops affecting the object.

A toy car is moving across a smooth floor. If you give it a gentle push in the same direction it is already moving, what will happen?

The car will reverse direction.

The car will continue at the same speed.

The helicopter will begin to move downward.

The helicopter will remain motionless in the air.

The helicopter will begin to move upward.

The helicopter's weight will increase.

The temperature of the air around the object.

Whether the forces acting on the object are balanced or unbalanced.

The exact weight of the object without considering other forces.