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Author Question: In the y-up, right-handed coordinate system, the positive z-axis points __________. (Read 29 times) |
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.
The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).