A researcher assembled two groups of individuals suffering from symptoms of the common cold. Group A was instructed to take a new supplement three times a day. Group B was simply advised to take over the counter remedies. At the end of the trial period, 90% of the individuals from Group A had less symptoms, and 25% of the individuals from Group B had less symptoms. a) Was this study observational or experimental? Why? b) What was the explanatory variable? What was the response variable?

A researcher assembled two groups of individuals suffering from symptoms of the common cold. Group A was instructed to take a new supplement three times a day. Group B was simply advised to take over the counter remedies. At the end of the trial period, 90% of the individuals from Group A had less symptoms, and 25% of the individuals from Group B had less symptoms. a) Was this study observational or experimental? Why? b) What was the explanatory variable? What was the response variable?

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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