历年真题：GRE试题1

　　19. According to the passage, late seventeenth- and early eighteenth-century　Chinese records are impor- tant for which of the following reasons?

　　(A) They suggest that the data on which the Maunder minimum was predicated were incorrect.

　　(B) They syggest that the Maunder minimum can- not be related to climate.

　　(C) Thcy suggest that the Maunder minimum might be \-'alid only for Europe.

　　(D) They establish the existence of a span of unusu- ally cold weather　worldwide at the time of the Maunder minimum.

　　(E) They establish that solar activity at the tirne of the Maunder minimum　did not significantly vary from its present pattern.

　　20. The author implies which of the followine about currently available geological and archaeoloeical evidence concerning the solar-activity cycle?

　　(A) It best supports the model of solar activity described in lines 37-45.

　　(B) It best supports the model of solar activity described in lines 45-52.

　　(C) It is insufficient to confirtn either model of solar activity described in the third paragraph.

　　(D) It contradicts both models of solar activity as they are presented in　the third paragraph.

　　(E) It disproves the theory that terrestrial weather and solar activitv are　linked in some way.

　　21. Tt can be inferred from the passage that the argu- ment in favor of the　model described in lines 37- 45 would be strengthened if which of the following　were found ta he tme?

　　(A) Episodes of intense volcanic eruptions in the distant past occurred in　cycles having very long periodicities.

　　(B) At the present time the global level of thunder- storm activity increases　and decreases in cycles with periodicities of approximately 11 years.

　　(C) In the distant past cyclical climatic changes had periodicities of longer　than 200 years.

　　(D) In the last century the length of the sunspot cycle has been known to　vary by as much as 2 years from its average periodicity of 11 years.

　　(E) Hundreds of millions of years ago, solar- activity cycles displayed the　same periodicities as do present-day solap-activity cycles.

　　22. lt can be inferred from the passage that Chinese observations of the Sun　during the late seventeenth and early eighteenth centuries

　　(A) are ambiguous BECause most sunspots cannot be seen with the naked eye

　　(B) probably were made under the same weather conditions as those made in Europe

　　(C) are more reliable than European observations . made during this period

　　(D) record some sunspot activity during this period

　　(E) have been employed by scientists seeking to argue that a change in solar　activity occurred during this period.

　　23. It can be inferred from the passage that studies attempting to use tree-ring　thickness to locate possi- ble links between solar periodicity and terrestrial　climate are based on which of the following assump- tions?

　　(A) The solar-activity cycle existed in its present form during the time period　in which the tree rings erew.

　　(B) The biological mechanisms causing tree growth are unaffected by short-term　weather pat- terns.

　　(C) Average tree-ring thickness varies from species to species.

　　(D) Tree-ring thicknesses reflecr changes in terres- trial climate.

　　(E) Both terrestrial climate and the solar-activity cycle randomly af~ct tree-ring　thickness.