Among the most common types of experiments are comparative studies that contrast outcomes under different conditions such as male versus female, placebo versus drug, or before versus after treatment.

Stool samples can help doctors diagnose some health conditions. Tips for collecting a stool sample include urinating before collecting the sample and using any tools that the sample kit provides.

Many types of businesses use product samples to allow potential and prospective customers to experience their products in hopes of enticing them to buy. Restaurants, for example, might offer free ...

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Precious moon samples brought back to Earth by China's Chang'e 5 mission in 2020 have finally been shared with international researchers — but the law has made it difficult for U.S.-based scientists ...