The correct answer is D. All the above.
The graphical method is a method of analyzing trusses by drawing a force diagram. The force diagram is a diagram that shows the forces acting on each member of the truss. The forces are represented by arrows, and the length of each arrow is proportional to the magnitude of the force. The graphical method is a quick and easy way to analyze simple trusses.
The method of joints is a method of analyzing trusses by considering the equilibrium of each joint. A joint is a point where two or more members of the truss meet. The method of joints involves drawing a free-body diagram for each joint. A free-body diagram is a diagram that shows all the forces acting on an object. The forces are represented by arrows, and the length of each arrow is proportional to the magnitude of the force. The method of joints is a more accurate way to analyze trusses than the graphical method.
The method of sections is a method of analyzing trusses by considering the equilibrium of a section of the truss. A section is a part of the truss that is bounded by two joints. The method of sections involves drawing a free-body diagram for the section. The forces are represented by arrows, and the length of each arrow is proportional to the magnitude of the force. The method of sections is the most accurate way to analyze trusses.
In conclusion, the forces in the members of simple trusses, may be analysed by A. Graphical method B. Method of joints C. Method of sections D. All the above.