Consider a three-machine scheduling problem where the machines are de- noted by A, B, and C, and each job must be processed in the sequence A B C. Suppose that min Ai max Bi or min Ci max Bi. Recall from Lecture 6 that John- sons algorithm can find the optimal sequence that minimizes the makespan by treating Ai = Ai + Bi and Bi = Bi + Ci as the processing times in a two-machine problem. Explain how this approach yields the optimal sequence when the number of jobs is two.