A system adopts a priority$-$based preemptive scheduling where the initial priority of a process increases by $1$ after every $5ms.$ In a recorded time span, the system has four processes, P$1,$ P$2,$ P$3$ and P$4,$ as shown in the following table:

$\backslash$table$[[\backslash$table$[[$PROCESS$],[$II$)]],\backslash$table$[[$INITIL$],[$PRIORTY$]],\backslash$table$[[$ARRIVAL TIVI$],[$IN US$]],\backslash$table$[[$TOTAL CPU TIME IN$],[$IS$]]],[P1,1,0,15],[P2,3,5,75],[P3,2,10,5],[P4,2,15,10]]$

Draw a timing diagram similar to Figure $3\mathrm{.}7$ and find the turnaround time for each process. Assume that the dispatcher takes $2\mathrm{.}5$ milliseconds for a process switch.