Modern CPUs need only a few to execute an instruction when all operands are in its registers.

Nanoseconds.

Explanation:

A scheduling computer system refers to an ability of the computer that typically allows one process to use the central processing unit (CPU) while another process is waiting for input-output (I/O), thus making a complete usage of any lost central processing unit (CPU) cycles in order to prevent redundancy.

Modern CPUs need only a few nanoseconds to execute an instruction when all operands are in its registers.

In terms of the scheduling metrics of a central processing unit (CPU), the time at which a job completes or is executed minus the time at which the job arrived in the system is known as turnaround time.

Generally, it is one of the scheduling metrics to select for optimum performance of the central processing unit (CPU).

b and c ( ip address and port number)