In simple terms if the question is mentioning the words distance or position it is highly likely to be a DEPARTURE related question, going east/west along a parallel of latitude.
So in your example,which funnily enough I worked through with a student yesterday. A to B is a departure question. So Dep = Ch Long (mins) x cos lat.
1 * 60 = 60 * cos 60 (.5) = 30 nm. However A to C is not departure as the positions are on the same meridian. It is testing do you know at 1 degree of Latitude is 60 nm so A to C = 60 nm.
Now if the question mentions the words like great circle, rhumb line, initial or final track highly likely to be a CONVERGENCY problem. I always teach my students tips similar to the ones mentioned.
Last edited by RichardH; 18th Oct 2012 at 12:06.