"'S e ur beatha ollaimh."
Translation:You are welcome, professor.
OK, I just figured it out after posting, but here is the explanation. Hopefully it can be helpful to others.
S' e do bheatha Iain =(Used when speaking to an older person or one not familiar with, More Formal)
S' e ur beatha Ollaimh= (Used when speaking to a younger person you are familiar with, ((or someone similar in age)) Less Formal)
The professor (formal)
Iain (more familiar)
I think it's the other way around. Do for familiar and Ur for polite.