Help! "Semicircle" country is invaded by so many right-angled triangles!
The army of the "Semicircle" country need your help.
They said: "∠AJH=156° and AJ=JH. ∠BAG and ∠BHG are separated into 5 equal parts. Their weakest part is at ∠DAH. If we able to determine the angle, we could destroy them immediately!"
So, help them to determine ∠DAH.