The cretaceous-tertiary extinction, the most famous of the big five, has been attributed to what major event(s) that triggered the extinction of the dinosaurs? an asteroid hitting the earth massive volcanoes erupting around the world rapid growth of forests on land surfaces falling sea levels increased competition from mammals

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.