Five batch jobs. A through $E,$ arrive at a computer center at almost the same time. They have estimated running times of $10,6,2,4$ and $8$ minutes. Their $($externally determined$)$ priorities are $3,5,2,1,$ and $4,$ respectively, with $5$ being the highest priority. For each of the following scheduling algorithms, determine the mean process turnaround time. Ignore process switching overhead.