Using Paper Plate To Measure Real Life Angles

Here's a branch from a tree in my back yard:

Here, I use the Paper Plate to measure the angle between to branches (Pics aren't accurate because I couldn't take the pic and hold the branch steady with one hand....)

The angle between the two branches is 35°  and  7π/36 rad

Here are two twigs coming up from the ground. (again, pictures aren't accurate measurements and the plate is upside down)

The angle between the two twigs is 75° and 5 π/12