31 . According to the passage, as the corona rays reach the planets, they become
(A) hotter
(B) clearer
(C) thinner£ 
(D) stronger

32. The paragraphs following the passage most likely discuss which of the following?
(A) The remaining layers of the Sun
(B) The evolution of the sun to its present form
(C) The eclipse of February 1 979
(D) The scientists who study astronomy

33.Where in the passage does the author compare the light of the Sun s outermost layer
to that of another astronomical body?
(A) Lines 2-3
(B) Lines 9-10
(C) Line 16
(D) Lines 22-23

Questions 34-42 .

£ £ £ Many of the computing patterns used today in elementary arithmetic, such as those for performing long multiplications and divisions, were developed as late as the fifteenth
century. Two reasons are usually advanced to account for this tardy development, namely,
the mental difficulties and the physical difficulties encountered in such work.

£ £ £  The first of these, the mental difficulties, must be somewhat discounted. The impression
that the ancient numeral systems are not amenable to even the simplest calculations is
largely based on lack of£ familiarity with these systems. It is clear that addition and
subtraction in a simple grouping system require only ability to count the number symbols of
each kind and then to convert to higher units. No memorization of number combinations is
needed .In a ciphered numeral system , if sufficient addition and multiplication tables have
been memorized , the work can proceed much as we do it today .

£ £ £  The physical difficulties encountered, however, were quite real . Without a plentiful and
convenient supply of some suitable writing medium, any very extended development of the
arithmetic process was bound to be hampered .It must be remembered that our common
machine-made pulp paper is little more than a hundred years old. The older rag paper was
made by hand and was consequently expensive and scarce.

34.What is the main purpose of the passage?
(A) To emphasize the importance of the mental process in performing calculations
(B) To explain why some elementary computing systems were not developed until the
fifteenth century.
(C) describe how ancient counting systems differ from those of the twentieth century
(D) To compare the mental and physical processes used in arithmetic

35. The word "tardy" in line3 is closest in meaning to
(A) historical
(B) basic
(C) unusual
(D) late

36. The word "these"in line 5 refers to
(A )patens
(B) reasons
(C) systems
(D)calculations

37. The word "discounted" in line 5 is closest in meaning to
(A) reduced
(B) contradicted
(C) disregarded
(D) interpreted

38. The author states that doing calculations in a simple grouping system requires
(A) memorizing numerical combinations
(B) using an adding machine
(C) producing large quantities of a writing medium
(D) converting number symbols to higher units

39. The word "encountered" in line 12 is closest in meaning to
(A) faced
(B) caused
(C) increased
(D) discussed

40. The word "hampered" in line l4 is closest in meaning to
(A) impeded
(B) concluded
(C) unnoticed
(D) rejected

41 . The author describes old rag paper as all of the following EXCEPT
(A) handmade
(B) costly
(C) scarce
(D) delicate

42. The passage supports which of the following conclusion ?
(A) Physical difficulties hindered the development of computing patterns .
(B) Memorizing addition and multiplication tables is necessary for most elementary
arithmetic processes .
(C) Most people experience mental difficulties in learning long divisions and in multiplications.
(D) Numeral systems invented before the fifteenth century could not have been used to
perform elementary calculations .

Questions 43-50 .

£ £  The ecosystems of the Earth provide an array of free public services that are essential for
the support of civilizations . They maintain the quality of` the atmosphere , provide food from
the sea. Manufacture and replenish soils, recycle wastes and nutrients, control the
overwhelming majority of crop pests and disease vectors, and so on.. People have no idea
how to take over these activities satisfactorily. They do know, however, that the theory once£ 
advanced in the nineteenth century - that the productivity of the land can he infinitely
increased by the application of capital, labor, and science- is wrong. History has shown
that once the natural life-support systems of a civilization have been sufficiently damaged,
they cannot usually be repaired. The ancient deforestation and overgrazing of the
Mediterranean region is a famous example. And today ,a global civilization is ruining the
global environment.

41, What is the main topic of this passage?
(A) Free public services
(B) Support needed for civilizations
(C) The vaule of ecosystems£ 
(D) The vastness of the Earth

44. The word "array" in line 1 is closest in meaning to
(A) large number
(B) excess
(C) requirement
(D) model

45.The word "They" in line 2 refers to
(A) ecosystems
(B) civilizations
(C) sea
(D) people.

46. Which of the following could NOT be included under the "free public services"
listed in lines 2-4?
(A) Preventing overgrazing by domestic animals
(B) Providing natural animals for harmful insects
(C) Creating and enriching material for plant growth>(D) Supplying air for breathing

47. The word "advanced" in line 6 is closest in meaning to
(A) debated
(B) ignored
(C) proved
(D) proposed

48. The author mentions the Mediterranean region as an example of
(A) the ability of nature to remedy human destruction
(B) the ability of people to make use of natural resources
(C) the manner in which people replenish the£ environment£ 
(D) the effects or human abuse of natural resources

49. The author suggests that civilizations can survive only if they
(A) greatly expand scientific research
(B) do not destroy the balance of natural processes
(C) replant the forests in the Mediterranean region
(D) invent new procedures to replace obsolete ecosystems

50. The author suggests that the difference between the ancient and the modern
situation is that today the problem is
(A) worldwide
(B) better understood
(C) more manageable
(D) economic