¡¡¡¡30. The word "they" in line 30 refers to
¡¡¡¡£¨A£© pregnant females and young
¡¡¡¡£¨B£© quarry operations
¡¡¡¡£¨C£© the value of the fossils
¡¡¡¡£¨D£© these factors
¡¡¡¡31.The phrase "account for" in line 33 is closest in meaning to
¡¡¡¡£¨A£© record
¡¡¡¡£¨B£© describe
¡¡¡¡£¨C£© equal
¡¡¡¡£¨D£© explain
¡¡¡¡32.Which of the following best expresses the relationship between the first and second paragraphs£¿
¡¡¡¡£¨A£© The first paragraph describes a place while the second paragraph describes a field of study.
¡¡¡¡£¨B£© The first paragraph defines the terms that are used in the second paragraph.
¡¡¡¡£¨C£© The second paragraph describes a specific instance of the general topic discussed in the first paragraph.
¡¡¡¡£¨D£© The second paragraph presents information that contrasts with the information given in the first paragraph.
¡¡¡¡33.Where in the passage does the author mentions the variety of fossils found at Holzmaden£¿
¡¡¡¡£¨A£© Line 1
¡¡¡¡£¨B£© Lines 3-5
¡¡¡¡£¨C£© Lines 12-13
¡¡¡¡£¨D£© Lines 19-21
¡¡¡¡Questions 34-41
¡¡¡¡The Lewis and Clark expedition£¬ sponsored by President Jefferson£¬ was the most important official examination of the high plains and the Northwest before the War of 1812. The President's secretary£¬ Captain Meriwether Lewis£¬ had been instructed to "explore the Missouri River£¬ and such principal streams of it as£¬ by its course and communication with the waters of the Pacific Ocean ¡may offer her most direct and practicable water communication across the continent£¬ for the purposes of commerce." Captain William Clark£¬ the younger brother of famed George Rogers Clerk£¬ was invited to share the command of the exploring party.
¡¡¡¡Amid rumors that there were prehistoric mammoths wandering around the unknown region and that somewhere in its wilds was a mountain of rock salt 80 by 45 miles in extent£¬the two captains set out. The date was May 14£¬ 1804. Their point of departure was the mouth of the Wood River£¬ just across the Mississippi from the entrance of the Missouri River. After toiling up the Missouri all summer£¬ the group wintered near the Mandan villages in the center of what is now North Dakota. Resuming their journey in the spring of 1805£¬ the men worked their way along the Missouri to its source and then crossed the mountains of western Montana and Idaho. Picking up a tributary of the Columbia River£¬ they continued westward until they reached the Pacific Ocean£¬ where they stayed until the following spring.
¡¡¡¡Lewis and Clark brought back much new information£¬including the knowledge that the continent was wider than originally supposed. More specifically£¬ they learned a good deal about river drainages and mountain barriers. They ended speculation that an easy coast-to-coast route existed via the Missouri-Columbia River systems£¬ and their reports of the climate£¬ the animals and birds£¬ the trees and plants£¬ and the Indians of the West - though not immediately published - were made available to scientists.
¡¡¡¡34.With what topic is the passage primarily concerned£¿
¡¡¡¡£¨A£© The river systems of portions of North America.
¡¡¡¡£¨B£© Certain geological features to the North American continent.
¡¡¡¡£¨C£© An exploratory trip sponsored by the United States government.
¡¡¡¡£¨D£© The discovery of natural resources in the United States.
¡¡¡¡35.According to the passage£¬ the primary purpose of finding a water route across the continent was to
¡¡¡¡£¨A£© gain easy access to the gold and other riches of the Northwest
¡¡¡¡£¨B£© become acquainted with the inhabitants of the West.
¡¡¡¡£¨C£© investigate the possibility of improved farmland in the West.
¡¡¡¡£¨D£© facilitate the movement of commerce across the continent
