Where are you on earth in each of the following? (a) the stars rise and set perpendicular to the horizon. (b) the stars circle the sky parallel to the horizon. (c) the celestial equator passes through the zenith (d) in the course of a year, all stars are visible. (e) the sun rises on march 21 and doesn't set until september 21 (ideally)

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.