A researcher studies the effect of exercise on stamina. Participants are randomly assigned to be in an exercise or no-exercise group for 12 weeks. Stamina is then measured by how long participants can walk comfortably on a treadmill. In this study, the dependent variable is:

Use the graph to determine the range. which notations accurately represent the range? check all that apply. (–∞, 2) u (2, ∞) (–∞, –2) u (–2, ∞) {y|y ∈ r, y ≠ –2} {y|y ∈ r, y ≠ 2} y < 2 or y > 2 y < –2 or y > –2

Let the mean of the population be 38 instances of from 6" - 9" hatchings per nest, and let the standard deviation of the mean be 3. what sample mean would have a confidence level of 95% or a 2.5% margin of error?

The tuition costs, c, for a local community college are modeled by c(h) = 250 + 200h, where h represents the number of credit hours taken. the local state university has tuition costs, s, modeled by the function s(h) = 300 + 180h. how many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.