1. Brooklyn, an astronaut in the year 2124, stands on a cliff 700 meters above the surface of a moon. She throws a rock up and over the edge of the cliff at a velocity of 11 meters per second. (a) (10 points) Brooklyn records that it takes 20 seconds for the rock to hit the ground below. Using this, show that the acceleration due to gravity on the moon is 4.6 m/sec2. (Hint: start by setting up and solving an initial value problem.) (b) (8 points) Brooklyn previously computed that the moon has a radius of 3000 kilometers. Using this information, determine the moon's mass.