Answer:
it was only 90 percent effective
Explanation:
In 1954 a massive controlled field trial was launched, sponsored by the National Foundation for Infantile Paralysis. Almost two million U.S. children between the ages of six and nine participated. In some areas of the country half of these “Polio Pioneers” received the vaccine, while half received a placebo. In other areas of the country children who did not receive any vaccine were carefully observed. On April 12, 1955, Thomas Francis, Salk’s mentor and the director of the trial, reported that the vaccine was safe, potent, and 90% effective in protecting against paralytic poliomyelitis.
The answer is none of the above because organic materials, gasses, and minerals are all component soils.
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The sentences that make sense are "Volatile liquids are flammable" and "Liquids burn easily."
Scanning Electron Microscope (SEM). Check Google next time lol
<span>the total amount of energy for a system stays the same, is the answer</span>
