For a population with an unknown distribution, the form of the sampling distribution of the sample mean is.

The authors use the word “backbone” in lines 3 and 39 to indicate that

Asking questions when something is unclear is part of?

When looking at research about instructional strategies, make sure the research is a. from peer-reviewed studies. b. approved by state and federal government organizations. c. online and easily accessible. d. about the same topic you're interested in.