Answer:
a) No, Joe is not correct. Since the angle 2 is opposite to the angle that measures 72°, 2 measures 72°. Since 72° + 3 = 180°, angle 3 measures 108°.
b) Below that we have the exactly same thing: angles 5 and 7 measure 72°, and angles 4 and 6 measure 108°.
Explanation: