Is it essential to kill operating system processes (in this case)? If so, when and how exactly will this be done? What is the basis for this, if not? How long after that do processes still exist?

This is an Operating system review question, answer the question by true or false. This is not a graded question because this is only a review question. Please explain also so that I could understand.

How can a computer system avoid wasting computing cycles that would otherwise be wasted when it performs more than one command at a time? Explain what happened as a result of what they did.

There is a computer system that intends to service multiple users. All tasks from the users have almost the same length (i.e. CPU time), usage of the system resources, and urgency. The tasks may arrive in the system at different time. During the execution, all tasks do not require user interventions. 1. What CPU scheduling algorithm would you choose? 2. Explain your choice.