A researcher is interested in determining theeffectiveness of a new medication that may reduce blood sugar levels for individuals who have diabetes and a higher than average blood sugar level. To determine the effectiveness of the medication, the researcher uses 100 volunteers who have diabetes. Volunteers are assigned randomly 50 milligrams of the medicine, 100 milligrams of the medicine, or a placebo. Blood sugar levels are measured at the beginning and end of the study.

Part A: Identify the subjects, treatments, and response variable.

Part B: What is the advantage of the random assignment of treatment?

Part C: What is an advantage of using a placebo?

Part D: What is a disadvantage of using volunteers?