a. Answer each of the following questions with a sentence or two. i. What is a daemon? State two roles that might be carried out by daemons. ii. What is the main idea behind a microkernel? iii. What is the benefit of using a 'salt' string in user passwords? iv. Why is simple contiguous allocation of blocks not used on hard disks? V. Give two advantages of using Bash scripts over commands entered on the command line. (10 marks) b. Outline what race conditions are, and how semaphores can be used to prevent access to critical regions. You should write no more than 100 words for this part of the question. (5 marks) C. FIFO, round-robin and priority are different techniques for scheduling processes. For each of these techniques, outline one shortcoming. (3 marks) d. The figure below shows a list of processes ready to execute. Draw three diagrams demonstrating how the FIFO, round-robin and priority schedulers would schedule these processes. The processes have arrived in the order given and have a priority (where 1 is the highest and 4 is the lowest priority). Process A requires one quantum, process B requires four quanta, process C requires two quanta, process D requires three quanta. (12 marks) Table 1 Processes Arrival order Priority D D D Last 1 3 B B B B 2 A First 4