The answer is: Eight grade
many scenes in famous literature such as Shakespeare contain actions, or themes that considered to be inappropriate if consumed by immature audiences. Eight grade is considered to be in the bare minimum since it's the time that students start undergoing puberty and able to understand mature themes.
I will do them one by one okay the 1st one is allergy
In an asthma attack, people have difficulties to breathe becuase the airway is reduced, the lungs excrete mucus, etc.
Answer:

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Answer:
Osteons are cylindrical structures that contain a mineral matrix and living osteocytes connected by canaliculi, which transport blood. They are aligned parallel to the long axis of the bone. Each osteon consists of lamellae, which are layers of the compact matrix that surround a central canal called the Haversian canal.