計算機結構與作業系統(B)

(8 pts) Given a set of $n$ processes, the arrival time of the $i$-th process is $(i - 1)$, and the burst time of the $i$-th process is $(2n - 2i + 2)$, as shown below:

Perform preemptive scheduling to minimize the average turnaround time (from the arrival time to the time of the completion of a process) of all processes. Assume that the minimized average turnaround time of all processes is $Wn^3 + Xn^2 + Yn + Z$. Select correct description(s).

（複選；至少一個正確選項，每個選項獨立計分。）