Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas. which group of statements best describe all of the materials he is using in the investigation?

Doctor a. d. aitchdey conducts research on childhood disorders. specifically, she wants to learn more about disorders in which the children's behaviors cause disruptions in their environments. her next project will focus on children with conduct disorder. in other words, doctor aitchdey's research is focusing on the category of childhood disorders.