2a°+2a°+2°+2a°+4°+2a°+6°+2a°+8°+2a°+10°+2a°+12°+2a°+14°=360°
16a°=360°-56°
16a°=304°
a=19⁰
a)
m(∡A₁OA₂)=19⁰×2=38°
m(∡A₄OA₅)=19⁰×2+6=44°
b)
masura unghiului format de bisectoarele unghiului A₁OA₂ si A₈OA₁
m(∡A₈OA₁)=19⁰×2+14=52°
adica m(∡A₁OA₂)/2+m(∡A₈OA₁)/2=38⁰/2+52⁰/2=90⁰