This question tests your knowledge of key concepts of operating systems.

a.Answer each of the following questions with a sentence or two.

i.What are the three types of access permissions for a file or directory?

ii.What is the difference between physical and virtual memory?

iii.What is the difference between an absolute file path and a relative file path?

iv.Why is contiguous allocation of storage not suitable on hard drives?

v.What is the difference between kernel mode and user mode?

(10 marks)

b.Outline the boot process of a system using UEFI. Highlight two benefits UEFI has over BIOS.

(10 marks)

c.Four processes A, B, C and D are ready to execute, having arrived in that order. They require different numbers of quanta to complete and request different priorities (1 is lowest, 4 is highest):

Process A requires 2 quanta, requested priority 1

Process B requires 5 quanta, requested priority 3

Process C requires 3 quanta, requested priority 2

Process D requires 4 quanta, requested priority 4.

What is the pattern of execution under the following scheduling strategies:

i.first in, first out

ii.round-robin

iii.priority.

Give your answer by showing which process executes at each quantum until all processes complete, for example: A C C B B

What is the total number of quanta required in each case?

(10 marks)