2.5 s
2.9 s
3.1 s
3.6 s
2.5 Mbits/s
4.25 Mbits/s
1.5Mbits/s
3.75Mbits/s
3
5
4
none of these
CPU protection
memory protection
file protection
all of these
meet prescribed time constraints
aim better resource sharing
aim better system utilization
aim low system overhead