Who is and who is not recommended to receive a flu vaccine? why do these recommendations exist?

answer for plato yw :)

Explanation:

People who can get the flu shot: Different flu shots are approved for people of different ages. Everyone should get a vaccine that is appropriate for their age. There are inactivated influenza vaccines (IIV) that are approved for people as young as 6 months of age. Pregnant women and people with certain chronic health conditions can get a flu shot.

People who should not get the flu shot: Children younger than 6 months of age are too young to get a flu shot. People with severe, life-threatening allergies to flu vaccine or any ingredient in the vaccine. This might include gelatin, antibiotics, or other ingredients.

These recommendations exist for the safety of people having different health conditions.

your answer is "the 1950's"

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

hope this