I assume you are talking about an exam in the US.  Norway just released an exam for drone operators as well.

 
All entertainments become source of income for producers. When selling drones is not enough they start invent courses and certificates.

I took it a few weeks ago and passed with a 94%.  I think I was way over-prepared.  I finished it in 28 minutes.

I subscribed to an online course that had plenty of practice quizzes.  This stuff is so dry, I think I needed someone visually explaining it rather than reading a book myself.

Biggest thing to look out for is the FAA trying to trick you.  Just go slow, concentrate, and always double check your figures.  They're known for putting common wrong answers as possible choices.

Good luck!

In Slovenia you don't need to make an exam to get allowance for flying drones like Phantom... but you can only fly these in empty terrain.

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