A drug company developed a pill to prevent air sickness and asked a researcher to test its effectiveness. For this purpose, the researcher obtained 200 volunteer subjects at a large airport terminal and asked them to participate in his study, testing the pill's effectiveness under rough flying conditions. Half of the volunteers on every trip were randomly chosen and given the pill. The other half were not given the pill. The flight attendants distributed the pill to those who were to receive it while they boarded the plane. Thus, the two groups were treated alike except that the subjects in the experimental group received a pill for air sickness and the control group did not receive a pill. Since 18% of the experimental group became air sick, and 76% of the control group became air sick, the investigator concluded that the pill was generally effective. Which TWO (2) of the following strategies would be most beneficial in improving her improve this experiment?

A drug company developed a pill to prevent air sickness and asked a researcher to test its effectiveness. For this purpose, the researcher obtained 200 volunteer subjects at a large airport terminal and asked them to participate in his study, testing the pill's effectiveness under rough flying conditions. Half of the volunteers on every trip were randomly chosen and given the pill. The other half were not given the pill. The flight attendants distributed the pill to those who were to receive it while they boarded the plane. Thus, the two groups were treated alike except that the subjects in the experimental group received a pill for air sickness and the control group did not receive a pill. Since 18% of the experimental group became air sick, and 76% of the control group became air sick, the investigator concluded that the pill was generally effective. Which TWO {2] of the following strategies would be most beneficial in improving her improve this experiment? Using a control group Blinding (e.g. make it a double-blind experiment) Using a placebo Blocking Repetition (more test subjects per treatment) Random assignment of treatements DDDDDD