A university conducts a series of surveys in which subjects are drawn from first year and graduating students and finds that graduating students demonstrate much higher rates of approval for the university (in terms of whether they think the classes were relevant, the instructors were competent, etc.). The university then claims that more experience with the university leads to higher approval. What source of internal invalidity has the university not considered?

In some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. the production of sterile male ligers is an example of read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. the production of sterile male ligers is an example of a postzygotic barrier the founder effect sympatric speciation a prezygotic barrier

What makes water a renewable source

Risk of harm in social and behavioral sciences generally fall in three categories, which are: breach of confidentiality, loss of autonomy, and study proceduresstudy procedures, breach of confidentiality, and loss of employmentinvasion of privacy, adverse reaction to study drug, and discriminationinvasion of privacy, breach of confidentiality, and study procedures