Angle Ranking: Near 90 or obtuse angles that are rotated strategies?

[DATtime]

These are the only angles I cant seem to get. Ive tried the pie, laptop, ski etc methods and I still sometimes get even the angles differing by 5 degrees wrong. Any tips on mentally rotating or another method?

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[NewtonStar]

I try imaging obtuse and right angles as chairs. The more reclined the chair is the bigger the angle.