Measure Supplementary Angles
 Use the half circle protractor to measure the angles.
 Type the angle of the red sector in the red box.
 Type the angle of the blue sector in the blue box.
 Press "add angles" to add the angles together. What should they add up to?
 Press "drive it" to see the turtle drive along the angle. Which sector shows the amount of turtle turn, the red one or the blue one?
 Press "new sectors" to measure a new pair of sectors.
