Researchers at Boston University examined the brains of 85 individuals who had received repeated trauma to the head. How many of them showed evidence of CTE?

Explanation:

Chronic traumatic encephalopathy :  

Chronic traumatic encephalopathy (CTE): this is a neurodegenerative condition associated with repeated injuries to the head.

According to the Boston University CTE Center, CTE is a degenerative brain disease found in military veterans,  athletes, and also in some others with a history of repetitive brain trauma.

Researchers at Boston University examined the brains of 85 individuals who had received repeated trauma to the head, 68 out of 85 showed evidence of CTE.

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%