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Challenge #16

Question 1.
There are traditionally six, basic, simple machines; the pulley, the inclined plane, the lever, and the wheel/axle are four of them. What are the other two ?
Question 2.
Troy weight is used to measure gold and silver and precious stones. (Other things are usually measured using the metric or avoirdupois systems.) How many ounces are there in a Troy pound. ?
In 1991 William Fenical, a chemist at the Scripps Institution of Oceanography in San Diego, went to the Philippines to hunt for organisms that might provide medically useful compounds. He found a two pound mass of Diazona chinensis in a cave 100 feet below the ocean surface. Back in San Diego he isolated, from its tissue, a chemical that killed colon cancer cells in laboratory tests.
  • Is Diazona chinensis a plant or an animal? And, to what taxonomic group of organisms does it belong?

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