Researchers investigated the possible beneficial effect on heart hea th of drinking black tea and whcther adding milk to the tea reduces any possible benefit. groups. Every day for a month, participants in group I dtici Twenty-four volunteers were randomly assigned to one of three without milk, participams cups of hot water but in group 2 drank two cups of hot black tea with milk, and no tea. At the end of the month, the researchers measur (a) Did the researchers conduc 1 drank two cups of hot black tea participants in group 3 drank two d the change in each of the participants' heart bealth. t an experiment or an observational study? Explain. (b) Why did the researchers include a group who drank hot water but no tea? (c) Is it reasonable to generalize the results of the study beyond the 24 participants? Explain why or why no