Question $1$: Consider the figure below and answer the following questions. Elaborate your answer supporting with evidence.

$($a$)$ Assuming FIFO service, indicate when packets $2$ through $12$ each leave the queue. What is the delay for each packet between its arrival and the beginning of the slot in which it is transmitted? What is the average of this delay over all $12$ packets?

$($b$)$ Assume a priority service where odd$-$numbered packets have high priority and even numbered packets have low priority. Indicate the time at which packets $2$ through $12$ each leave the queue. What is the delay for each packet between its arrival and the beginning of the slot in which it is transmitted? What is the average of this delay over all $12$ packets?

$($c$)$ Now assume round$-$robin service. Assume that packets $1,2,3,6,11,$ and $12$ are from class $1,$ and packets $\backslash (4,5,7,8,9\backslash ),$ and $10$ are from class $2.$ Indicate the time at which packets $2$ through $12$ each leave the queue. What is the delay for each packet between its arrival and departure? What is the average delay over all $12$ packets?

$($d$)$ Now assume weighted fair queueing $($WFQ$)$ service. Assume that odd$-$numbered packets are from class $1,$ and even$-$numbered packets are from class $2.$ Class $1$ has a WFQ weight of $2,$ while class $2$ has a WFQ weight of $1.$ Note that it may not be possible to achieve an idealized WFQ schedule as described in the text, so indicate why you have chosen the particular packet to go into service at each time slot. For each packet what is the delay between its arrival and its departure? What is the average delay over all $12$ packets?

$($e$)$ What do you notice about the average delay in all four cases $($FIFO$,$ RR$,$ priority, and WFQ$)?$