5видов вопросов к he studies zoology at university

What he studies at university?
Where he studies zoology?
Who studies zoology at university?
He studies zoology at university, is not it?
How much times he studies zoology at university?

What does he study at university?
does he study zoology?
where does he study zoology?
he studies zoology, doesn't he?
who does study zoology?