$7.$ Compare the results for the two$-$workstation line from Part B to this four$-$workstation line. From the videos, note how they differ in terms of blocking and starving, as well as the resulting line output. Hypothesize how the number of workstations might moderate $($a$)$ the relationship between variability and workstations$$ utilization, and $($b$)$ the relationship between variability and line output.