Answer: New vaccines are offered each year because the virus changes.
Explanation: The flue viral strain constantly changes its genetic make up, a process called antigenic drift. As the virus replicates there are small changes that creates new strains which evolve to a completely different influenza virus requiring a new type of vaccine each year.
Answer:
A) Bowling ball
Explanation:
Because a bowling ball has more mass than a basketball.
<span>if you increase concentration of one side it will shift to the</span>gv
Answer:
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Explanation:
