Use the Following Information for Following Questions

Essay

Use the following information for following questions:. Which treatment is most effective at
treating bathroom mildew: water mixed with vinegar, ammonia, or soap? In a study, researchers randomly
assigned 55 similar tile samples with similar amounts of mildew to one of three groups. Depending on
which group they were assigned to, each tile sample received a home remedy of water mixed with
vinegar, ammonia, or soap. Afterwards, each tile sample was examined and any remaining mildew was
measured. Researchers found that a soap and water mixture produced better results than both vinegar and
ammonia.
-Is this a controlled experiment or an observational study? Explain.