You are an intern at a small CPA firm in your hometown. The owner$/$managing member, Gochin, knows that you recently earned an A in your AlS course. Later today, he has a meeting with a potential client, who specifically wants an explanation of the main types of information systems and their functions. He asks you to give him a refresher before he goes to the meeting. Briefly explain to him the four main types of information systems and their functions.