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Author Question: Why might sodium carbonate (washing soda, Na2CO3 ) be added to hard water to aid in cleaning? A) ... (Read 98 times) |
The familiar sounds of your heart are made by the heart's valves as they open and close.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Cucumber slices relieve headaches by tightening blood vessels, reducing blood flow to the area, and relieving pressure.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Asthma-like symptoms were first recorded about 3,500 years ago in Egypt. The first manuscript specifically written about asthma was in the year 1190, describing a condition characterized by sudden breathlessness. The treatments listed in this manuscript include chicken soup, herbs, and sexual abstinence.