1) The document discusses an experiment to test if gravity affects small and large marbles differently when rolled down an inclined surface. Students use a ramp made of books or a binder and observe whether the marbles hit the ground at the same time or if one is faster. 2) The document also discusses other examples of forces, such as magnetism and gravity. Gravity makes all objects attract each other, with stronger attraction between larger objects. 3) Students are asked to predict whether heavy objects will fall faster than light ones based on the idea that heavier objects feel they are pulling harder against hands, and to consider how to test their prediction.