6. When a process runs, there are four measures of time that are useful, wall-clock-time, user-time, kernel-time, and wait-time. (a) (4 points) Define each of these four kinds of time and explain how they relate to the process states (from problem 3). (b) (6 points) Suppose a system has very few processes in existence and one process is "I/O bound" and is doing a lot of reading and writing to a disk. Explain what kind of relationship you would expect to see between the four times for this process. (c) (6 points) Suppose a single core system has very few processes in existence and one process is "CPU bound" and makes no system calls. Explain what kind of relationship you would expect to see between the four times for this process.