Nosebleeds Having a nosebleed is a common occurrence. Children experience epistaxis when blood flows out from either or both nostrils, often for a short period of time. It may be caused by one's behavior like frequent nose picking or blowing too hard when one has a cold. It may also be caused by certain physical factors such as an allergy or abnormal growths in the nasal cavity. Or it may be due to environmental conditions such as exposure to toxic fumes or dryness of the air. While it is often thought that holding one's head back can treat a nosebleed, this can actually cause one to choke or vomit. The best thing to do is to lean forward, pinch the top of the nose and apply a cold compress. And if that doesn't work, it's best to get professional help.

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Nosebleeds Having a nosebleed is a common occurrence. Children experience epistaxis when blood flows out from either or both nostrils, often for a short period of time. It may be caused by one's behavior like frequent nose picking or blowing too hard when one has a cold. It may also be caused by certain physical factors such as an allergy or abnormal growths in the nasal cavity. Or it may be due to environmental conditions such as exposure to toxic fumes or dryness of the air. While it is often thought that holding one's head back can treat a nosebleed, this can actually cause one to choke or vomit. The best thing to do is to lean forward, pinch the top of the nose and apply a cold compress. And if that doesn't work, it's best to get professional help.

21. Which of these options help treat a nosebleed?

A. pinching the nostrils shut

B. applying a cold compress on the nose

C. applying a warm compress on the nose

D. holding the head back to keep the blood from flowing

B. applying a cold compress on the nose

Explanation:

The text shows that despite being a common situation, nasal bleeding is still treated incorrectly, as people believe that tilting the head back is the best way to stop the bleeding. However, this practice is very harmful and dangerous, and the correct thing to do is to tilt your head forward, squeeze the top and apply a cold compress.

answer: b (host)

viruses use the cells of living organisms to reproduce. the cell which is used by virus is called as "host cell". it is a living cell in which virus multiplies, example bacteria, plant or an animal cell.

in this, the virus is a parasite, which uses host cell for its benefit (reproduction) by using the cell machinary of host cell.

the cost of attendance or coa is an approximate budget for the cost of attendance of the whole academic year. in order to calculate this, universities take into consideration many factors like room and board, tuitions and fees, books, transportation and personal expenses such as medicine, laundry, clothing. all these factors combined make up the final sum to the cost of attendance in each university.