Two jobs must be processed through a five$-$machine shop. The processing times are shown

below. The routing of the jobs are as follows:

$J_1=>M_4,M_5,M_1,M_3,M_2$

$J_2=>M_5,M_4,M_2,M_3,M_2$

a$)(20$ points$)$ Using the graphical approach, find the minimum makespan schedule, and

interpret it$.$ What is the value of $C_{mrx}?($Solving by other methods will not be evaluated$))$

b$)(5$ points$)$ Calculate the total waiting times of $J_1$ and $J_2.$