How can tight muscles result in back pain?
a.
they contain sensitive nerves that become painful when tight.
b.
they can constrict the nerves in the spinal column.
c.
tight muscles stretch surrounding tissues and organs.
d.
they improve posture, which results in back pain.

Match each child care option with its benefits. a. no child care expenses b. likely to have values similar to those of the parents c. lots of one-on-one time with a provider d. care offered at schedule hours 1. family member or friend 2. private child care 3. day care 4. stay at home parent

How quickly a drug enters your bloodstream also depends on

[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.