Questions, questions

Been re-reading “Towards Dialogic Teaching” (Alexander) and “Asking Better Questions” (Smith). I've been asking questions but only a very limited range:
Who knows the answer?
What is the answer?
Is that the right answer?
Who agrees with....?
So I'm going to try to use a wider range of questioning techniques from Monday onwards –
How do you know that's the answer?
Can you explain to me why that's the right answer?
Can you tell the class how X has come to that answer?