Categorize the following systems as S-, P-, or E-systems. For each one, explain why it belongs in that category. Identify those aspects of the system that may change.
(a) an air traffic control system
(b) an operating system for a microcomputer
(c) a floating-point acceleration system
(d) a database management system
(e) a system to find the prime factors of a number
(f) a system to find the first prime number larger than a given number