What are the different forms of communication flow taking place in this scenario?

Sara Lang, a charge nurse at Sunny Nursing Home, has worked under the same president, Lisa Davis, for 5 years. In fact, the two have become good friends. They frequently socialize after hours. Rick Walters, director of nursing, is a capable person who has been working there for 3 years. Four nurses (Anna, Barbara, Charles, and Dan) report directly to Sara.