Experiment on Mice A scientist who studied 40 mice wondered if he was feeding them food that would make them gain the most weight. He usually feed the mice 10 corn pellets each every day. He wondered if he changed the diet to wheat, if the mice would gain weight. So he fed 20 of the mice 10 corn pellets every day and the other 20 mice 10 wheat pellets everyday. The weight of the mice was recorded everyday for a month. 24. What is the manipulated variable? 25. What is the responding variable? Color of the mice Food Amount of water Weight