he sum of the forces acting on an object is called the resultant or net force. an object is said to be in static equilibrium if the resultant force of the forces that act on it is zero. let f⇀1=⟨10,6,3⟩,f⇀2=⟨0,4,9⟩ , and f⇀3=⟨10,−3,−9⟩ be three forces acting on a box. find the force f⇀4 acting on the box such that the box is in static equilibrium. express the answer in component form.