Mr. Kline's earth science class set up an experiment to compare the heating and cooling rates of sand and water. They filled cups with sand and water and then recorded the temperature change while (a) a light was shining directly on the cups and (b) the light was turned off. The data one group collected is presented in the data table. Based on this data, we would expect ___________ to have the greatest changes in temperatures during a 24-hour period.