What was the hardest question you experienced during the oral part of your
Private exam?

The only question I didn't answer correctly was the difference between an
alternator and a generator. Boy do I feel stupid about that. The DE later
told me that I had given the best oral exam he had done in years and that is
why he started asking all kinds of unusual questions about electrical
systems and such. Then he laughed at me for missing such an easy question
after answering a bunch of other much harder ones. Basically it was an EE
giving a ChE a hard time.

[Good thing my oral was good, I don't recall my practical being very good.]