In 1998, paleoanthropologist rick potts published an article in the yearbook of physical anthropology, a peer-reviewed journal. the article was titled “environmental hypotheses of hominin evolution.” isabel wonders if she can cite this article as a valid scientific reference. which statement below best answers her question?

a. the article is not valid because it was not published this year.
b. the article is not valid because it contains no supporting evidence.
c. the article is valid because it was reviewed by other scientists.
d. the article is valid because potts is a renown paleoanthropologist.

This map shows how climate change might affect precipitation patterns in the great plains of the united states by the end of this century. brown shoes a decrease in percipitation, and blue shows an increase. the maps differ based on the predictive levels of green house emissions. the maps shows that northern area should get a. more pracipations regardless of emmissions b. less pracipation, regardless of emmissions levels c. more precipitation, but only when emission levels. southern areas show a. more pracipations regardless of emmissions b. less pracipation, regardless of emmissions levels c. more precipitation, but only when emission levels. to use these maps to prepare for natural disasters in the great plains, scientist need to ask? a. how many tons of emissions were used at the basis of the map. b. which types of fossil fuels are used in the great plains c. if you think the above is wrong it's probly c the question is cut off

Which of the following statements best distinguishes a hypothesis from a theory? a. theories are hypotheses that have been proved. b. hypotheses are guesses; theories are correct answers c. hypotheses usually are relatively narrow in scope; theories have broad explanatory power. d. theories are proved to be true; hypotheses are often contradicted by experimental results.

The hershey and chase experiments involved the preparation of two different types of radioactively labeled phage. which of the following best explains why two preparations were required? a. the bacteriophage used in the experiments was a t2 phage. b. it was necessary that each of the two phage components, dna and protein, be identifiable upon recovery at the end of the experiment. c. each scientist had his own method for labeling phage, so each conducted the same experiment using a different isotope. d. establishing the identity of the genetic material required observation of two phage generations.