One question that scientists have not yet answered is what caused the number of large zebra mussels to decline. How might tracking different parts of the ecosystem over a long time help scientists to answer this question?

Who built the first turnpikes in the united states? a) the national government b) state governments c) private companies d) town councils

Micah is studying child behavior in playgrounds throughout the world. he wants to see how the children react when teachers select the same child to be the first to use each piece of equipment. which approach is micah is using?

Suppose you are a freshmen in college and you have not declared a major. one reason you enrolled at your respective college was the school's vibrant social life. at the same time, you want to balance your academic life because you know that your grades will matter for graduate school or job applications.you decide to forgo partying for two hours to study for an upcoming economics exam. in your first semester's principles of economics class, you learn that the enjoyment you would have received from partying is an example of a(n)