A helicoptor leaves an army base and flies 60 km on a bearing of 278 degrees
a) how far west has the helicoptor flown?
b) how far north has the helicoptor flown?

It helps to draw a diagram. Note that 278 derees is a bit more than 270 degrees, and since 270 degrees is due west, the helicopter in this problem is flying a bit north of due west. Draw his route as the hypotenuse of a right triangle, with the base along the east-west axis. The angle the triangle makes to the east-west axis is 278 - 270= 8 degrees; do you see whay that is? From this, for question (a) how would you find the length of the base of a traingle whose hypotenuse is 60 Km in length and that makes an 8 degree angle to the base? For (b), how would you find the height of such a triangle? Think cosines and sines.