Question

how to measure the angle of 3D shapes​

Answer 1

Looking at the small triangle that includes angle b we now know that a = 35° and, since the sum of the triangles equal 180° we can find angle b. Angle c and the 95° angle are supplementary; they add up to 180°. Now we know c = 85° we can find angle d since the three angles in the triangle add up to 180°.