Your answer is B) 35π/18.
The size of angle x is equal to π/18, which you find by doing π/2 - 4π/9 because π/2 is the size of a right-angle in radians.
However, as this is not an available option, I believe the question is asking for the size of the angle subtended by the red arrow. You can find this by doing 2π, which is 360° in radians, minus π/18. This gives you 35π/18, which is option B.
I hope this helps!
