Using a protractor to measure angles
(For assistance see www.mathopenref.com/constmeasureangle.html)
1.   The figure below is an irregular triangle.
  (a) Measure the 3 internal angles with a protractor and add them up.
  (b) Challenge Problem: Determine the sum of the interior angles of a triangle using knowledge about the properties of triangles, and verify your measurements. (Hints at: www.mathopenref.com/triangleinternalangles.html)