Suppose an exercise scientist wants to estimate the proportion of american adults who exercise for 30 minutes three or more times per week. she wants to construct a 90% confidence interval with a margin of error of 1%. what sample size does she need?

fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges. the core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in.