Identifying Variables When planning an investigation, it is important to identify the variables in the procedure. The independent variable is the one you will change, while the dependent variable is the one that will respond to the changes. And of course, you need to have controls so that you are doing a fair test Identify the variable for this investigation A. Amount of algae added to beakers B. Color of liquid in each beaker C. Amount of liquid in each beaker D. Percentage of fertilizer E. Amount of light 1. Controls 2. Dependent Variable 3. Independent Variable