ill try to describe it the best i can
i would say 30 degrees fonr the middle piece. what im saying is that if you have you middle flat section and you were to draw an invisible line over where the up and down part will be make the angle from that to the rail part 30 degrees.
does that make sense???
if it doesn't i'll draw a picture to show you
about 10 degrees, trust me. I had one that was around 20 and it was way too steep, i had to flatten it out. It should also be a minimum of 15 feet long. I would recommend each section being about 7 feet long. Mine is about 5 ft per section and its good, but i wish it was a little longer
My brother took these last year after we made it less of an angle.