When tackling a problem in equilibrium, always keep in mind that all forces in any direction are all balance out. Let us imagine that this 180 kg crate is being held by a wire. The Force "p" necessary to put this crate in equilibrium will be the tension on wire acting upward. Remember that weight "W"is a force, and force according to Newton's law is equal to mass multiply by acceleration. F=W=mg. The total force needed to balance the mass is simply Force "p=mg". Therefore the magnitude of the force will be just multiplying mass and the normal pull of gravity, equivalent to 9.8m/s².