Answer:
how many boys to girls there are. in china there is a drastic difference between the two which can/will cause future population shrinkage issues
The reason why one case of influenza does not confer lifelong immunity is that the virus tends to mutate overtime which makes it unrecognizable to the immune system.
<h3>Why is it difficult to get immunity to influenza?</h3>
Influenza is caused by a virus which tends to mutate overtime in order to stay ahead of medical technology.
As a result, this mutation makes the original virus unrecognizable to the immune system which would then be unable to fight it.
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C. River Valleys.
There was much more vegetation and fertility.
The arthropod phylum is the largest phylum of the animal kingdom, including among others all the species of lobsters, insects, crabs, spiders and centipedes. Contrary to popular belief, animals belonging to this phylum exhibit a wide range of behaviours. Parental skills or care is a term related to the behaviours involving the protection of eggs and young.
Several species of insects, look after their eggs over the winter and when the eggs hatch, the young stay with their mother, for feeding and protection.
Some species of spiders and scorpions, hold their eggs in a web formation and once they hatch, they hold them on their back until they are able to survive by themselves.
1) - removing barriers to trade does not protect from foreign influence - false.
2) regional trade blocks are usually correlated with decreasing, not increasing tariffs - false.
3) this it true - and this is the reason - correct answer
4) it increased, not reduces diffusion- not the correct answer
