How would you try to reduce the number of head concussions in a sport? It can be football

Your answer is  d.)relationship between pressure and air volume and led to the understanding of how respiration works

You can literally find this on google of each science career and search up what type of training you need and how many years in school

Depression is lifelong, though you can get medication to with it. the difference between sadness and depression is that sadness lasts a little bit, depression last a long time and it goes on and off. people usually get depression through experiences they have been through, or genetics.