We had four different test tubes and in each we put ¾ of each solution; one with sucrose, one with glucose, one with water, and one with starch. After putting in the solution, we measured out one gram of yeast and put it into the test tube with the solution. After putting in the yeast, we filled the rest of the test tube with the same solution we used before. When the test tube was filled, we put our thumb over it and tipped the solution up and down to mix the solution. We then took a big test tube and placed it over the small test tube containing the solution. We tipped it upside down and placed it in the test tube rack, and we marked where an air bubble was forming. We did this three more times with the rest of the solutions. After all the solutions were done, we put them in the oven for 20 minutes. After 20 minutes was up, we took them out and measured where the air bubble was now and compared it from before going into the oven and after.