A man is using a platform attached to a rope to climb the exterior wall of a building. As shown in the diagram, the platform is suspended from one end of the rope, and the man is sitting on it. The man is pulling on the other end of the rope to move upwards. The man's mass is 75 kg, and the platform's mass is 25 kg. The force exerted by the man on the platform is 300 N. Find the acceleration of the man and the platform as they move upwards.