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[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.

Match the following. biodegradable diabetes n hazardous w cancer ozone 1. the layer of the atmosphere that the ozone layer is part of the type of wastes that can be broken down by other organisms into a reusable form the type of solid, liquid, or gas wastes that are toxic, flammable, corrosive, reactive, or radioactive the process by which certain waste materials, such as plastic, glass, aluminum, and paper are prepared for reuse 5. the addictive drug found in tobacco a disease frequently developed by smokers and passive smokers a disease of the pancreas in which insulin is not produced in 7. the correct amounts so that glucose can be converted into energy or stored as fat formed in the atmosphere when chemicals, called volatile 8. organic compounds (vocs), and nitrogen dioxide (no2) are acted upon by sunlight when burned, it can cause an increase of co2, ozone, and sulfur dioxide in the atmosphere stratosphere fossil fuel recycle nicotine

Select the correct answer. which is the safest and most effective way to get a deeper stretch? a. massage the muscles being stretched b. inhale and push the stretch until it hurts c. lean into the stretch as you exhale d. place ice on your muscles before stretching