There are six jobs in a factory. All these jobs have to go through two workstations for processing. Each job is processed on Workstation #$1$ and then on Workstation #$2.$ The processing time for each job on each workstation is given below.

$\backslash$table$[[$Job$,$Time on Workstation #$1($minutes$),$Time on Workstation #$2($minutes$)],[1,25,11],[2,50,25],[3,10,39],[4,13,20],[5,43,50],[6,13,9]]$

Using Johnson's sequencing rule, it can be concluded that the makespan of the sequence is:

a$.$ more than $115$ but less than or equal to $140$ minutes.

b$.$ more than $140$ but less than or equal to $160$ minutes.

c$.$ more than $160$ but less than or equal to $180$ minutes.

d$.$ more than $180$ but less than or equal to $205$ minutes.