Greetings and Responses

What do you say when someone greets you with 'Hello'?

If someone says 'Good morning', how should you respond?

When someone says 'How are you?', what is an appropriate reply?

If a friend greets you with 'Hey!', what can you say back?

What is a suitable response to 'What's up?'?

If someone says 'Good evening', how do you reply?

When greeted with 'Hi there!', what is a good response?

If someone says 'Long time no see!', how should you respond?

What do you say when someone greets you with 'Howdy'?

If a classmate says 'Nice to see you!', what can you say in return?