From my observations, AOB looks like an isosceles triangle, so A=18 and B=18. Since a triangle must add up to 180. We do 180-18-18=144. O= 144. Then, triangle BOC looks like an isosceles triangle as well. So, we do 180-144= 36 so O = 36 and then we 180-36=144/2 because two sides have the same angles giving us 72 degrees for angles B and C = 72 and for O= 36
