A 4.51-kg object is thrown vertically upward from the surface of Earth, where the acceleration due to gravity is g1 = 9.81 m/s2. The initial velocity is v1, and the object reaches a maximum height of y1. What is the maximum height, y2, if the object is thrown with a speed of v2 = 1.39v1 from the surface of the Moon? The acceleration due to gravity on the Moon is g2 = 1.62 m/s2. Give your answer as a multiple of y1.