Some students investigated the effect of pH on the action of the enzyme trypsin. Trypsin breaks down a protein found in milk. This turns the milk into a clear, colourless solution. The students set up five test tubes. Each test tube contained trypsin and milk at either pH 5, 6, 7, 8 or 9. The students then timed how many minutes it took for the milk in each test tube to turn colourless. Design a table that could be used to record the results for this investigation. (3)