Well I can't be for sure but I know for a fact its not set IV it's not possible to make a triangle out of all right angles. Set II, well, that isn't right either. You can't make a triangle out of all obtuse angles. Like the right angle one, its not possible you can only use one obtuse or right angle in a triangle other wise it's not going to be a triangle. I'd say go try Set III since that would most likely make an equilateral triangle.