Question $1$: $[\_\_/9]$ Consider the arrival of nine packets to an output link at a router during the time interval $[0,5].$ Time is divided into "slots," beginning at t $=0,1,2,3,$ and so on$.$ Packets can arrive at any point during a slot, and multiple packets may arrive within a single slot. At the start of each time slot, the packet scheduler selects one packet from the queued packets $($if any$)$ for transmission, using a round$-$robin scheduling method. Each packet requires exactly one slot to transmit, meaning that a packet selected for transmission at time t will complete its transmission at t $+1.$ At that point, another packet will be chosen for transmission from those queued. As mentioned earlier, packet scheduling employs a round$-$robin method, prioritizing three traQic classes $(1,2,3),$ with lower classes receiving higher transfer time priority. Based on this scenario answer the following questions: $1.$ At t$=1,$ which packet is sent out? Give the packet number. $2.$ At t$=2,$ which packet is sent out? Give the packet number. $3.$ At t$=3,$ which packet is sent out? Give the packet number. $4.$ At t$=4,$ which packet is sent out? Give the packet number. $5.$ At t$=5,$ which packet is sent out? Give the packet number. $6.$ At t$=6,$ which packet is sent out? Give the packet number. $7.$ At t$=7,$ which packet is sent out? Give the packet number.