A call center has four categories of employees, each paid a particular wage. Managers are paid $25 an hour, clerks are paid $15 an hour, technicians are paid $20 an hour, and administrative assistants are paid $13 an hour. The call center has 2 managers, 20 clerks, 4 technicians, and 5 administrative assistants. a. What is the simple arithmetic average of the hourly rates? b. What is the weighted average of the hourly rates? Round to the nearest cent