Victory for the ACT Student Text 15e

V ICTORY P RACTICE T EST A NSWERS AND E XPLANATIONS • 473

30. (H) (p. 415) Science/Evaluation of Models/Analysis . š’‡”‹‡– Ͷ •Š‘™• –Šƒ– ˆ”‹…–‹‘ ƒˆˆ‡…–• –Š‡ ”‡Žƒ–‹˜‡ ƒ……‡Ž‡”ƒ–‹‘ between the box and either the sled or ball. Calculate the acceleration for the box: d at 1 2

2

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a

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25 ( )

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0. ft/sec 8 ‡…ƒ—•‡ –Š‡ ‘‹Ž‹‰ ‹ š’‡”‹‡– Ͷ…ƒ—•‡† ƒ…Šƒ‰‡ ‹ –Š‡ „‘šǯ• ƒ……‡Ž‡”ƒ–‹‘ǡ ˆ”‹…–‹‘ ‹• ƒ ˆƒ…–‘”Ǥ ‘ŽŽ‹‰ —•– also be a ˆƒ…–‘” ƒ• ’‡” –Š‡ ƒ•™‡” ‡š’Žƒƒ–‹‘ –‘ ‹–‡ ͓ʹͻǤ 31. (A) (p. 415) Science/Interpretation of Data/Comprehension . The acceleration of the ball is constant at 3.5 ft/sec 2 (either š’‡”‹‡– ͳ ‘” ͶȌǤ Š‡ ƒ……‡Ž‡”ƒ–‹‘ ‘ˆ –Š‡ •Ž‡† ‹•…‘•–ƒ– ƒ– 4.9 ft/sec 2 ȋ š’‡”‹‡– ʹ ‘” ͶȌǤ Š‡”‡ˆ‘”‡ǡ –Š‡ ratio of the ball’s acceleration to the sled’s acceleration is . . 4 9 3 5 7 5 . 32. (H) (p. 415) Science/Interpretation of Data/Comprehension . Although the acceleration of the ball is relatively insensitive to the amount of friction, the acceleration of the box is very sensitive to friction. Therefore, in a ratio, the effect of changing the amount of friction will change the numerator (ball acceleration) only slightly, whereas the †‡‘‹ƒ–‘” ȋ„‘š ƒ……‡Ž‡”ƒ–‹‘Ȍ ™‹ŽŽ…Šƒ‰‡ •‹‰‹ϐ‹…ƒ–Ž› †‡’‡†‹‰ ‘ ˆ”‹…–‹‘Ǥ ‘–‡ –Šƒ– ȋ Ȍ ‹• ‘–…‘””‡…– „‡…ƒ—•‡ the acceleration remains constant within each experiment. 33. (B) (p. 416) Science/Evaluation of Models/Analysis . Scientist 2 concludes by saying that Neanderthals and early modern humans merged into a single species by interbreeding, so Scientist 2 assumes that the two groups were •—ˆϐ‹…‹‡–Ž› •‹‹Žƒ” –‘ ’‡”‹– ‹–‡”„”‡‡†‹‰ ‘ˆ –Š‡ ‡„‡”•Ǥ ȋ Ȍ †‹•–‘”–• –Š‡ ’‘•‹–‹‘ ‘ˆ…‹‡–‹•– ʹǤ…‹‡–‹•– ʹ •ƒ›• that the picture we have of the Neanderthals is based upon one individual, an individual who was not entirely representative of his species. In other words, the one Neanderthal with arthritis was the exception, not the rule. (C) also misreads the passage. Scientist 2 says that populations were spread out geographically, not that the two groups were separated physically from one another. (Indeed, they must have lived pretty close to each other to permit the interbreeding that Scientist 2 believes occurred.) Finally, as for (D), though Scientist 2 says that Neanderthals were ƒ’’ƒ”‡–Ž› ‘”‡ —•…—Žƒ” –Šƒ ‡ƒ”Ž› ‘†‡” Š—ƒ•ǡ –Š‹• †‘‡• ‘– ƒ—–‘ƒ–‹…ƒŽŽ› ‡ƒ –Šƒ– –Š‡› ™‘—Ž† ™‹ ƒ ϐ‹‰Š–Ǥ Speed, intelligence, weapons, and a lot of other factors might affect the outcome. 34. (H) (p. 416) Science/Evaluation of M dels/Analysis . For early modern humans to completely replace Neanderthals, there could not have been a region containing Neanderthals that did not also contain early modern humans. 35. (D) (p. 416) Science/Evaluation f Models/Analysis . The discovery of evidence of an isolated community of ‡ƒ†‡”–ŠƒŽ• ™‘—Ž† ‘– ‡…‡••ƒ”‹Ž› ™‡ƒ‡ ‡‹–Š‡” Š›’‘–Š‡•‹•Ǥ Š‡ –Š‡ –™‘ •…‹‡–‹•–• –ƒŽ ƒ„‘—– ’‘’—Žƒ–‹‘• „‡‹‰ dispersed, they are not saying that the individuals were perfectly distributed—like so many salt and chlorine atoms in a water solution. A pocket of Neanderthals here or a concentration of early modern humans there would not be inconsistent with the general distribution pattern described. 36. (J) (p. 416) Science/Evaluation of Models/Analysis . This information suggests that early modern humans killed Neanderthals, which supports Scientist 1. 37. (C) (p. 417) Science/Evaluation of Models/Application . This fact shows that even if two species can breed, they may not do so voluntarily. Scientist 1 can therefore use this case as an example of the fact that two genetically compatible but dissimilar-looking animals choose not to interbreed. (D) is not readily relevant because lions and tigers are „”‘—‰Š– –‘‰‡–Š‡” ƒ”–‹ϐ‹…‹ƒŽŽ›Ǥ ‘ ‘‡ †‹•’—–‡† –Š‡ ‘–‹‘ –Šƒ– ƒ‹ƒŽ•…ƒ ‹–‡”„”‡‡†ǡ •‘ ȋ Ȍ †‘‡• ‘– ‡–‡” –Š‡ argument. (B) is incorrect because lions and tigers do not share the same niche (tigers are solitary forest hunters while lions are group-hunting plains dwellers), and their ranges rarely overlap. 38. (H) (p. 417) Science/Evaluation of Models/Comprehension . The mixing of traits is part of Scientist 1’s objections to Scientist 2’s hypothesis.