Answer all please and thank

[120 total points] (public health) in one of the largest human experiments ever conducted, in 1954 a randomized controlled trial was run to see whether a vaccine developed by a doctor named jonas salk was effective in preventing paralytic polio. a total of 401,974 children (ages 6–9), chosen to be representative of those who might be susceptible to the disease, were randomized to two groups: 200,745 children (the control group c) were injected with a harmless saline solution (a placebo) and the other 201,229 children (the treatment group t) were injected with salk’s vaccine.what was the point of giving saline solution to the children who didn’t get the vaccine? explain briefly.

You're in the breakroom at work when you see a coworker posting a cartoon on the bulletin board. you read it as you pass, and it's a joke about women breastfeeding in public. a male walks up, looks at it and starts laughing. other make employees walk up, and one takes it down saying he is going to make copies for everyone. what do you do?

Bulimia nervosa cannot be prevented, but it can be treated if diagnosed early. true or false?