For the arch shown in Figure P7.4, the thrust force exceeded the abutment's lateral su...

For the arch shown in Figure P7.4, the thrust force exceeded the abutment's lateral support capacity, which is represented by a roller at C. Load P was removed tem­porarily and tension rod AC was added. If the maximum compression in members AB and BC will be 750 kips, what size diameter tension rod is required? (Ignore dead load of the arch.) The allowable tensile capacity of the rod is 32 ksi. Determine the reactions.