The UAVCoach drone school was very helpful, passed test, and did well. Registered online so that I can submit application in next day or two once they get exam info loaded on site. Confused as I thought everything was capable of being done online, but reading on site talks of face to face meeting with a CO, before a digital signature could be applied to the application. Explanation please,. I have made no contacts with a FAA official for this meeting.
Just took FAA test, cats test today. Course very helpful in my getting a great score. Think your question is indicative of some of the tricky ones on the actual test. I believe the difference in the two answers you question is: one addresses the frost on the surface and its effects. The other actually claims the frost has somehow changed the properties of the propeller, or wing. Good luck!