For number 7:
a) The sum of the adjacent angles is 180. Because if its any three angles thats half of the angles all together 3/6 = 180/360.
b) The sum of the angles in the center is 360 degrees. Because 60 x 6 = 360.
c) The unknown angles (center angles) are 61.25 degrees.
For number 8 (bonus):
It's C) 90 Degrees, because it's a right angle.
Hope this helps :)
