Question 1 (40 pts) Suppose the hypothetical processor of the given Figure 1 (left one) also has two I/O instructions: (i) 0011 = Load AC from I/O, and (ii) 0111= Store AC to I/O. In these cases, the 12-bit address identifies a particular external device. Show the program execution using format of Figure 1 (right one) for the following program: Figure 1: Characteristics of a hypothetical machine and an example of program execution. 1. Load AC from device 5 . 2. Add contents of memory location 940 . 3. Store AC to device 6 . Assume that the next value retrieved from device 5 is 3 and that location 940 contains a value of 2. Question 2 1. (20 pts) What is the purpose of system calls, and how do system calls relate to the OS and to the concept of dual-mode (kernel-mode and user-mode) operation? Question 3 (40 pts) Figure 2 contains seven states. In principle, one could draw a transition between any two states, for a total of 42 different transitions. Figure 2: Process state transition diagram 1. List all of the possible transitions and give an example of what could cause each transition. 2. List all of the impossible transitions any explen ? hy