17.                                                                                                       The track at A is the

                                                                                                            angle Pole-A-B.

                                                                                                            From inspection we

                                                                                                            note that it is less

                                                Pole                                                     than 90º.

                                          060ºW       060ºE                                       Consider triangle

                                                                                                            Pole-A-B:  distance

            A: 70ºN                                                                                   Pole-A = Pole-B so

            060ºW                                                             B: 070ºN          angle A = angle B.

                                                                                    060ºE               Angle at pole =

60º + 60º = 120º,

000º E/W                                             Therefore angles A

                                                            and B are 30º.