Figure 3 shows the apparatus the student used. Figure 3 PH meter Thermometer ON OFF PH sensor Fresh milk Computer This is the method used. 1. Set up the apparatus as shown in Figure 3 with the milk at 20 .C. 2. Record the pH over 5 days using the computer. 3. Repeat with another batch of fresh milk at 25 .C. |2 Give one variable the student should keep constant. Do not refer to temperature in your answer. Question 2 continues on the next page