Assistant Sales / Trader

I applied online through the career centre website of my university (I am at EDHEC Business School, Nice, France)
I first got a call which lasted for 40 minutes where the interviewer asked for my background, what I did in my previous internship (I was Portfolio Manager Assistant in a startup). I got no technical questions here.
Then they asked me to come to their office in Geneva (the nice thing is that they paid for the airplane ticket) and the interview lasted for 4 hours, I have been interviewed by all the employee. It was either personality, background and even technical questions.
They didn't print my CV so I had to explain my curriculum everytime, as I saw the employees one by one.
The question on my background were very basics (where do I come from, why did I choose finance, etc.)
Regarding the technical questions, it was mostly about derivatives (the company I was applying for is a broker, on derivatives and structured products) :
- basics questions on futures prices (you can find them in the Hull)
- Questions on the time value, intrisic value of a call/put and its underlying. Why isn't the curve straight ?
- I also got some mathematical questions : cdf and pdf of a normal distribution, i have been asked to derive the pdf, give the standard deviation, the mean.
- and finally some IQ questions "what is the exact angle made by the needles of a clock at 15:15 ?" (answer : 7.5°) "if you have three buttons and the rooms and each button switch on the light of one single room, how can you determine which button switch on which room ? You cannot see the light and you are allowed to go to the rooms just once" (Answer : it's with the heat of the light : switch one on for a long time as the light will get very hot, another one for a short time, and you touch the light to see which one is right).
As I mentioned earlier, I saw all the employees. They are various and very different. Some of them are really nice and want you to progress and learn, some of them are just here to intimidate. Even if I had a bad experience there, I must recognize that the employees looked very implied and qualified in their job.