the ecosystem of the hilly region seems to be rich? what are the causes? what should be done in the future to conserve the ecosystem? explain.

Every person’s body is different, a. but every vehicle’s cabin layout is the same b. and every vehicle’s cabin layout is different c. making some people automatically safe drivers d. making some people better fit to drive a sedan than a coupe

Why would a smoker tend to inhale more deeply and smoke more cigarettes when he or she switches to low nicotine cigarettes

[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.