A triangular truss is to be built. It will consist of a horizontal member AB, with A attached to a wall and B supported on a roller at a point 20 m away. The third joint, C, needs to be 10 m above AB. It will be subjected to 500 kN of force horizontally in the direction from A to B. If C can be placed above any point along the member AB, where should it be put to minimize the largest force on the truss? (b) Repeat the question above, but this time with the force on C being angled down by 30˚