From Mechanics

The vertical components of the forces on the tank cancel out.

The resultant of all the forces on the tank is thus the resultant of the horisontal components of the forces.

Maximim friction is \displaystyle 836\ \text{N} and acts horisontally to the left.

The horisontal component of the 5000 N force is \displaystyle 4531\ \text{N} and acts to the right.

The resultant of these two forces is \displaystyle 3695\ \text{N}