Q32

Consider four processes $\text{P, Q, R,}$ and $\text{S}$ scheduled on a $\text{CPU}$ as per round robin algorithm with a time quantum of $4\text{ units.}$ The processes arrive in the order $\text{P, Q, R, S,}$ all at time $\text{t = 0}.$ There is exactly one context switch from $\text{S}$ to $\text{Q},$ exactly one context switch from $\text{R}$ to $\text{Q},$ and exactly two context switches from $\text{Q}$ to $\text{R}.$ There is no context switch from $\text{S}$ to $\text{P}.$ Switching to a ready process after the termination of another process is also considered a context switch. Which one of the following is $\text{NOT}$ possible as $\text{CPU}$ burst time $\text{(in time units)}$ of these processes?