What is the ability to contract a muscle, or group of muscles, repeatedly without getting tired?

What is an important step to prove something is valid or not? determining the reliability observing research testing

Select the correct answer. which of these is a valid minimum educational requirement to pursue a career as a family resource coordinator? a. phd in child psychology b. bachelor's degree in social service c. experience working with school children d. basic training in child therapy reset next

[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.