USAAAO — 2019 First Round

Two amateur astronomers A and B living in Ecuador are standing on the Equator at the Galapagos Islands (height 0 m, longitude 91° W) and at a sea-level site near Volcán Cayambe (height 0 m, longitude 78° W) respectively. What are the differences (in degrees) of the altitudes from the horizon and zenith distances of the Sun measured by these two astronomers on March 20, 2019 when it is local noon for observer B? Neglect refraction and give your answer to the nearest degree. [Updated from the original exam, which placed observer B at 5790 m, to remove an ambiguity about the horizon dip.]