Q41

Consider the following four processes with arrival times (in milliseconds) and their length of CPU bursts (in milliseconds) as shown below:

$$\begin{array}{|c|c|c|c|c|} \hline \text{Process} & P1 & P2 & P3 & P4 \\ \hline \text{Arrival Time} & 0 & 1 & 3 & 4 \\ \hline \text{CPU burst time} & 3 & 1 & 3 & Z \\ \hline \end{array}$$

These processes are run on a single processor using preemptive Shortest Remaining Time First scheduling algorithm. If the average waiting time of the processes is $1$ millisecond, then the value of $Z$ is _____