Answer:
O=30° or O=29°
Step By Step Explanation:
∠α =arcsin( a/c )
= arcsin(4/8)
= arcsin(0.5)
= 0.5 rad = 30° = 29°
I Hope This Helps. I Gave you 2 answers just in case 1 is Wrong. And I Hope you Understand This Calculation, I Used Different Variables and the arcsin thing is something my teacher told my class to use, and I Have no Idea what it means because my teacher never explained what it meant, Sadly.