Based on what should I use mı, mu and müdür?! Generelly not just in this sentence.
In this case it is implied by the mu and mi. Yoksa could also have been used.
Could you also use "veya"?
Are "yoksa" and "veya" interchangeable?
In the meantime I have been reading the following (hoping I'm right):
'veya' is used when there are more than two options you can choose.
'yoksa' is used when there are only two options, the translation can be 'or' respectively 'if there is not'.