HELP PLEASE i really do not understand the concept?

Consider a child of mass 40 kg standing on the roundabout at a radius of 0.5 m from the centre. The roundabout rotates with a time period of 5.0 seconds. The child is holding a ball and throws it straight up into the air whilst he is on the roundabout. Describe and explain how the ball will travel through the air and where it will land.