(A) abysmal : low
(B) cogent : contentious
(C) fortuitous.: accidental
(D) reckless : threatening
(E) cataclysmic : doomed
14. WORSHIP : SACRIFICE ::
(A) generation : pyre
(B) burial : mortuary
(C) weapon : centurion
(D) massacre : invasion
(E) prediction : augury
15. EVANESCENT : l)ISAPPEAR :
(A) tlansparent : penetrate
(B) onerous : struggle
(C) feckless : succeed
(D) illusory : exist
(E) pliant : yield
16. UPBRAlD : REPROACH ::
(A) dote : like
(B) lal: : stray
(C) vex : please
(D) earn : desire
(E) recast : explain
Directions: Each passage in this group is followe by questions based on its content. After reading a passage, choose the best answer to each question. Answer all questions following a passage on the basis of what is stated or implied in that passage. lt has been known for many decades that the appear- ance of sunspots is roughly periodic, with an average cycle of eleven years. Moreover, the incidence of solar flares and the flux of solar cosmic rays, ultraviolet radia- tion, and x-radiation all vary directly with the sunspot (5)
cycle. But after more than a century of investigation. the relation of these and other phenomena, known collec- tively as the solar-activity cycle, to terrescrial weather and climate remains unclear. For example. the sunspot cycle and the allied rnagnetic-polarity cycle have been (10)
linked to periodicities discerned in records of such vari- ables as rainhll. temperature, and winds. lnvariably,however, the relation is weak. and commonly ofdubious statistical significance. Effects of solar variability over longer terms have also (15)
been sought. The absence of recorded sunspot activity in the
notes kept by European observers in the late seven- teenth and early eighteenth centuries has led some schol- ars to postulate a brief cessation of sunspot activity at that time (a period called the Maunder minimum)。 The (20)
Maunder minimum has been linked to a span of unusual cold in Europe extending from the sixteenth to the early nineteenth centuries. The reality of the Maunder mini- mum has yet to be established, however, especially since the records that Chinese naked-eye observers of solar (25)
activity made at that time appear to contradict it. Scien- tists have also sought evidence of long-term solar period- icities by examining indirect climatological data, such as fossil recoras of the thickness of ancient tree rings. These studies, however, failed to link unequivocally terrestrial(30)
climate and the solar-activity cycle, or even to contirm the cycle's past existenue. If consistPn! and re!iab!e geo!sgigal~-arek-xologieal evidence tracing the solar-activity cycle in the distant past could be found, it might also resolve an important(35)
issue in solar physics: how to model solar activity. Cur- rently, chere are two models of solar activity. The tirst supposes that the Sun's internal motions (caused by rotation and convection) interact with its large-scale magnetic field to produce a dynamo. a device in which(40)
mechanical energy is converted into the energy of a mag- netic field. ln short. the Sun's large-scale magnetic field is taken to be self-sustaining, so that the solar-activity cycle it drives would be maintained with little overall changc for perhaps billions of years. The alternative(45)
exp)anarion supposes that the Sun's large
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