4 1. D 2. F 3. A ACT Science 1, Set 2 Answers & Explanations Both scientists agree that this caused their extinction; the disagreement is in the manner of things that actually blocked out the sun. The other answer choices do not have much to do with the ideas behind Scientist 1’s assertions. The basis of Scientist 2’s argument is that a ‘mantle’ plume is a more likely cause than asteroid impact. 4. H When you refute something, you prove it false. If there was volcanic ash, the asteroid theory would have to be false. 5. C Nothing confirms a theory like a repeat of the event that was supposed to have happened! 6. J The crater would confirm that a large asteroid can hit the earth. 7. B These plumes will probably be the same as those that killed the dinosaurs. 8. F Even though Scientist 2 does not like the plastics, s/he never refutes their benefits to man. 9. A While looking at someone’s motivation, it is helpful to consider who might be paying for the opinion. One never wants to publish a negative opinion of the person that is paying you. 10. H While there is disagreement about the relative safety, there is no disagreement about the usefulness. 11. D This is the only syndrome of the choices that has been possibly attributed to the use of phthalates and PVC, according to the passage. 12. J The disorders that were mentioned are not common at all among children, but 4 only happen later. 13. D Both of the scientists agree, to different degrees, that care should be taken in genetically modified planting. 14. J Scientist A’s argument was against genetically modified organisms, but if they were going to be used, the scientist argued that the consumer should be able to choose if they want to eat them or not. 15. A Scientist B believes that they have been tested enough and are fit for consumption. 16. G Scientist B argues that they have been tested and that they are safe while Scientist A argues that they haven’t been studied longitudinally. 17. C Scientist A thinks the genetically modified organisms are different from the original while Scientist B does not. 18. H Scientist B argues that using genetically modified foods will allow farmers to grow food more efficiently, yielding a larger harvest in a smaller area. 19. A Scientist B approves of the way that they have been tested and goes on to support testing of any new material created. 20. F Scientist B is concerned that the leakage of hydrogen will ultimately undo all of the good we’re trying to do with the hydrogen cars. If hydrogen isn’t really going to be released, then it isn’t something to worry about, but that’s something that should be studied, according to Scientist B. 21. B If cars are being powered by hydrogen, they are not using oil. 22. J Scientist A is very fond of hydrogen cars and argues fervently in their favor. He or she ACT HOMEWORK SCIENCE 1, SET 2 1 4 would like to see some on the road. 23. C Scientist B does admit this is quite the variable, but does not really give an answer to it, only that it needs more study. 24. F Since hydrogen produces water, its byproducts can be released harmlessly, unlike carbon monoxide ACT HOMEWORK SCIENCE 1, SET 2 2 4