Jamie completes the following steps in an experiment to investigate how temperature affects how fast something will rust in water. He places a nail in a bowl of water in the sun and a nail in a bowl of water in the shade. He also leaves an iron nail out of the water in a dry bag out of the sun. Why would Jamie leave one out of the water and out of the sun?  Jamie also wants to test if the water affects how fast the iron nail will rust. Jamie notices that the size of the nail is different, so he does not want to use it later. Jamie doing all these steps to create a control group to compare his results to. Jamie puts the nail in a cooler place to see if it will rust as fast as the other items.