List three (3) types of supervisory communication List three (3) ways to communicate without speaking or writing List three (3) barriers to effective communication List three (3) barriers to efficient communication List three (3) ways to develop effective communication techniques List three (3) reasons to hold meetings (rather than communicating individually) List three (3) costs associated with holding meetings List three (3) benefits associated with holding meetings List three (3) problems encountered during meetings List three (3) ways to enhance the effectiveness of meetings