One. They're efficient and don't have humour.
A reich cake
He heils a taxi!
I don't know, it's not my side work.
None. Anything not completed during the lesson is added to the homework.
None they can't change anything.
One, but he wishes it was two.
A: An Canadian not only has a sense of humour but can also spell it.
Prism (Note: I made this joke up. Sorry if this little note refracts from the humour.)