Wow. This question is very, very challenging for a "Primary 3" question. Seems like I have to revise my "Primary 3" work once again. Or am I in the 30th century where the Primary 3 syllabus includes trigonometry? Hmmm...

(Well, it may have really been a Primary 3 question after all)

In any case, I have redrawn the diagram because the two angles in the diagram given appear very disproportionate, misleading and flawed. The 211 degrees one seems to look more like something around 260 to 265 degrees, while the 305 degrees looks like 340 to 345 degrees. Refer to my diagram, it's more accurate than the given diagram.

Let me know if you need further explanation on the concepts.