Answer:
Well, I'm not the smartest person, nor do I exactly know what you mean, but I have a wild guess that the least you could rotate it is 100 degrees.
Explanation:
Considering the fact that it's sides are all equal, you could compare this to a square, which also has equal sides. Its angles are equal, too, so you could measure it's angles (100 degrees) and turn it that exact amount,
I hope this helps you, like I said, I don't exactly know what you are talking about, I am not studying that sort of thing yet.