What four areas should always be addressed in a team charter? Why is it a good idea to create a team charter?

What four areas should always be addressed in a team charter? Why is it a good idea to create a team charter?200 words pleaseNote: To address the issues of goals, purpose, and approach in your team launch by creating a team charter, action plan and work plan.A charter usually consists of 1) project purpose/goals 2) team member roles and responsibilities 3) ground rules 4) communication protocol