Many of these questions are pretty straight forward, and you've probably heard them before - but keep in mind, whether or not someone remembers the intonation tendencies of various secondary instruments are skills they can look up and learn as they grow into a better music educator. My belief is that you want to make sure you have someone you can work with in order to achieve large goals, grow your program, and enjoy spending more time with than your own family in the band world.
So, some suggestions of relatively easy questions for them, but easy traps for them to fall into would be things like:
1) Describe a typical class. What would I see?
2) Describe a challenging teaching situation (difficult student, students weren't learning) and how you overcame it.
3) How do you choose music for your students for the fall (marching music, stand tunes, fall concert), for UIL, and for the spring?
4) What do you view your role as an assistant band director to be?
5) When you disagree with the head director, how do you respond?