Exercise 4a

Implemented set-priority scheduling for Exercise 4a.
Exercise 5

Answered Exercise 5.
Exercise 6

Implemented atomic printing with system call for Exercise 6.
Fixed Set-Priority

Fixed set-priority scheduling to properly alternate between
equal-priority processes.
Exercise 4b

Implemented proportional scheduling for Exercise 4b.
Exercise 8

Implemented alternative synchronization with locks for Exercise 8.