Which of these is an advantage of an ultrasound over an x-ray

Discuss lexy's path to anorexia by putting the events that let to her anorexia in sequential order.

[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.

What is the longest you should ice the injured area at one time? a. 10-20 minutes b. 30-60 minutes c. 1-2 hours d. as long as you want