Read each scenario and determine which variables are independent and which ones are dependent. [2 marks each] a. A graph shows how long a student's sleep affects exam grades. Length of time spent sleeping Exam grade b. A study was done to determine which brand of fertilizer is best for plants. The health of the plants The brand of fertilizer c. Compare brands of paper towels to evaluate which holds the most liquid. The volume of liquid The brand of paper towel d. The amount of food you consume affects how much you weigh The amount of food