Use the Following Information for Following Questions

question 21

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.

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Definitions:

Electrical Impulse Sensors

Devices used to detect and measure electrical signals, often utilized in medical diagnostics and monitoring.

Spirometer

An instrument that measures the air taken in and expelled from the lungs.

Lungs

Pair of respiratory organs in the chest of vertebrates where blood is oxygenated.

Air

The unseen mixture of gases that envelops the Earth, primarily composed of oxygen and nitrogen.