Question 1903Navigation General

The correct answer is A) 011°W. The longitude of the lower vertex of a great circle track is opposite to the longitude of the upper vertex. Since the longitude of the upper vertex is 169°E, the longitude of the lower vertex must be 011°W. This is because the total span of a great circle is 180 degrees, so the opposite longitude from 169°E is 011°W. The other answer choices are incorrect because: B) 101°W is not the opposite of 169°E. C) 169°W is the same as the upper vertex, not the lower vertex. D) 076°E is not the opposite of 169°E.