A system runs a good mix of I/O-bound tasks and CPU-bound task. On one instance, there were 5 I/O-bound tasks and 6 CPU-bound tasks. Assume that the I/O-bound tasks issue an I/O operation once for every two millisecond of CPU computing and that each I/O operation takes 10 milliseconds to complete. Also assume that the context-switching overhead is 0.5 millisecond and that all processes are long-running tasks. Describe the CPU utilization for a round-robin scheduler when:

a. The time quantum is 1 millisecond

b. The time quantum is 10 milliseconds