List of top Computer Science Questions on Operating Systems - Process Synchronization

Which of the following synchronization mechanisms allows multiple processes to safely access a shared resource?
What is the average waiting time for the following CPU workload using Round Robin method with a time slice of 4 ms (assuming that all jobs arrived at the same time)?

Process No.Next CPU burst time in ms
A5
B7
C4
D9
Which of the following problems can occur due to improper process synchronization?