As a consultant to a local manufacturing facility, you are conducting a leadership training seminar. you encounter several managers who believe that they can describe the key to their success: manager a says that he is successful because when he tells a subordinate to do something, "they do it because i'm the boss and that's that!" manager b explains that she can get her employees to do what she wants because they like her and they want the manager to like them. manager c feels that his employees are cooperative because they realize that he knows more about how to do their jobs than anybody else in the plant. manager d says that all the others should use her secret: "if i can't get someone to work, i just take away their leave privileges and that corrects that problem!" manager a is exhibiting which type of power?