An object with a mass of 6.0 kg accelerates 4.0 m/s² when an unknown force is applied to it. what is the amount of force ?

Gravity, from the center of mass of the box, extending downward normal force, from the floor under the box, extending upward, equal to gravity push force, acting at a point on the box, extending in the direction of motion friction, acting at any point on the box directly opposite the push, extending directly opposite to the motion