Marco Polo was the trader that traveled from Venice, Italy to China and brought back information about Asia. Marco Polo was a Venetian merchant traveler. His father was the person from whom he learned the ways of mercantile trade. He did travel to China but he was not the first person. he made a detailed description in his books.
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.
Find out more on natural immunity at brainly.com/question/21480961
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She is diagnosed of having a phobic disorder where a person could feel a enormous amount of fear in a particular activity or an object that would trigger his or her fear. The type of phobia of which she is likely experiencing which is a fear of heights is called acrophobia.
