Answer Explanations

PASSAGE 1

1. Hi. Section A explains the origin and development of the CT scanner.

2. vii. Section B talks about how CT scanners were developed to work faster

so that images were less distorted and patients were more comfortable.

3. ix. Section C explains the process of getting X-ray images of the patient.

4. ii. Section D explains the computer systems used for CT scans.

5. viii. Section E talks about the different circumstances for which CT scans

are used.

6. x Section F explains the use of dyes to make CT scan images easier to analyze.

7. v. Section G talks about possible dangers to patients receiving CT scans.

8. (B) Section A: “The computed tomography scanner, better known as the CT

scanner, was originally designed to provide cross-sectional images of the brain.”

9. (D) Section A: “Godfrey Hounsfield developed the technique in 1972. . . .”

10. (E) Section B: “While the original CT scans took Hounsfield several hours

to reconstruct into a useful image. . . . ”

11. (B) Section F: “During ‘dynamic CT scanning,’ iodine dye is either

injected into the blood. . . .”

12. (D) Section F: “Patients who receive contrast material in the arm often

report feeling a warm sensation. . . . ”

13. (F) Section F: “in rare cases an allergic reaction occurs.”

PASSAGE 2

14. (B) Paragraph 1: “In America, dime novels. . . .”

15. (A) Paragraph 1: “while British penny bloods (later called penny dreadfuls)

told serial tales of horror or fictionalized versions of true crimes.”

16. (A) Paragraph 3: “penny bloods featured tales of gore that often depicted

the upper class as corrupt.”

17. (C) Paragraph 1: “thus providing inexpensive entertainment for the masses.”

18. (B) Paragraph 1: “dime novels typically centered on tales of the American

Revolution and the Wild West. . . . ”

19. (C) Paragraph 1: “A publishing craze that hit both America and England

from the mid- to late nineteenth century attracted the readership of the

semiliterate working class.”

20. (C) Paragraph 2: “In 1870, the Forster Education Act made elementary

education mandatory for all children.”

21. (F) Paragraph 3: “In the original story, String o f Pearls: A Romance, published

in 1846, Sweeney Todd. . .

22. (A) Paragraph 5: “In I860, Beadle and Adams was the first firm in the

United States to publish a title that would be categorized as a dime novel.”

23. (E) Paragraph 5: “The International Copyright Law, passed by Congress in

1890, required publishers to pay royalties to foreign authors.”

24. Yes. Paragraph 2: “by the 1830s, approximately 75 percent of the working

class had learned to read.”

25. No. Paragraph 2: “Though few children's books were available. . . .”

26. No. Paragraph 3: “Controversy still exists over whether Thomas Prest’s

character was based on a real person.”

27. Yes. Paragraph 5: “during the Civil War, soldiers quickly became the most

avid dime novel readers.”

PASSAGE 3

28. (I) Paragraph 1: “Astronomers found that it accurately predicted all the

observable data . . ., with one exception—a very slight variation in the orbit

of the planet Mercury around the sun.”

29. (B) Paragraph 3: “Among other phenomena, Einstein’s theory predicted

the existence of black holes.”

30. (F) Paragraph 3: “Black holes are areas in space where the gravitational

field is so strong that nothing can escape them.”

31. (A) Paragraph 3: “they can be studied only by inference based on observations

of their effect on the matter—both stars and gases—around them and

by computer simulation.”

32. (L) Paragraph 3: “when gases are being pulled into a black hole, they can

reach temperatures up to 1,000 times the heat of the sun. . . . ”

33. (D) Paragraph 4: “Because observations of event horizons are difficult due

to their relatively small size, even less is known about them than about black

holes themselves.”

34. (C) Paragraph 5: “Compact ones . . . are believed to be the result of the

death of a single star.”

35. (B) Paragraph 6: “Current scientific data suggest that black holes are fairly

common and lie at the center of most galaxies.” Choice (A) is contradicted

by the information in paragraph 6. Choice (C) is confused with the mention

of the sun, but it is used to describe the size, not the location, of a back hole.

36. (A) Paragraph 6 explains that Sagittarius A* is a black hole in the center of

the Milky Way and 26,000 light years from Earth. Choice (B) uses words

from the paragraph, but black holes do not orbit Earth. Choice (C) is incorrect

because the paragraph tells us that Sagittarius A* is a super-massive, not

a compact, black hole.

37. Not Given. The big bang is mentioned, but the time of its occurrence is not.

38. True. Paragraph 7: “A number of theories proposed that the first black holes

were essentially “seeds,” which then gravitationally attracted . . . matter . . . .

This allowed them to grow into the super-massive black holes.”

39. False. Paragraph 7: “The new simulations do not definitively invalidate the

seed theory, but they make it far less likely.”

40. False. Paragraph 7: “it is known that black holes a billion times more massive

than our sun did exist in the early universe.”