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问题 选择题

下列现象中，属于与多风气候相适应的现象是（　　）

A．蛾类夜间活动

B．仙人掌的叶变成刺

C．候鸟的迁徙

D．山顶的旗形树

答案

在高山和海岸边，我们常常会见到这样的一些树木--它们的枝叶只生长在树干的一侧，远看就像一面绿色的旗子插在地上，这就是旗形树．在盛吹定向强风的地方，有一些树木向风面的芽体由于受风的袭击而损坏，或者过度蒸发而造成死亡，因此向风面不长枝条；而背风面的芽体则因受风的影响较小而存活较多，虽然能生长枝条，但也比正常树木的枝条少很多．有的树木，它的向风面虽然能长出枝条，但这些枝条也因受风的压力影响而弯向背风的一侧…这些原因，使得这一带的树木基本上都变成了旗形树．因此旗形树冠是盛吹定向强风形成的．选项A是光的影响；选项B是水分的影响，选项C是温度的影响．

故选：D

单项选择题

2000年4月，第九届全国人大第十五次常委会，通过新修订的（），阐明了“超标即违法”的思想，使环境标准在环境管理中的地位进一步明确。

A.《中华人民共和国环境保护法（试行）》

B.《中华人民共和国大气污染防治法》

C.《中华人民共和国固体废物污染防治法》

D.《中华人民共和国水污染防治法》
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单项选择题

Questions 21～25


While other members of my team explored the wreck of a small Greek merchant ship that sank off the Turkish coast more than 2,400 years ago, I hovered above them in a submarine. One diver, an archaeologist, placed an amphora, or two-handled jar, inside a lifting basket. Another vacuumed sediment from the site by fanning sand into the mouth of a nearly vertical pipe. Two more were taking measurements, carefully, but of necessity quickly, for at this depth each diver had only 20 minutes to complete the morning’s assigned task. Any longer, and they would require lengthy medical treatment, to avoid the divers’ ailment known as the bends.
In four decades of diving on shipwrecks, I’ d been too engrossed in carrying out similar tasks to think of the families whose loved ones may have disappeared long ago. I had always concentrated on the technical features of my trade. I had stopped diving regularly 15 years before this exploration, turning over the bulk of the underwater work to a younger generation, but I continue to make inspection dives on most wrecks we excavate.
This was not just any wreck. Although I’ve been involved in uncovering the remains of much older ships, and of more than a hundred ancient shipwrecks along the Turkish coast. I had never even seen a wreck from the fifth century BC. Preliminary photographs of the cargo dated it to the third quarter of the century, during the Golden Age of classical Greece. Athens, then as now the major city in Greece, controlled an empire stretching from one side of the Aegean Sea to the other. None of this would have been possible without naval might and maritime commerce.
During our three-year exploration of the wreck we excavated examples of nearly every type of jar that the classical Greeks made for wine or water. Many types might have been used as tableware by the ship’s crew, but they were far in excess of what would have been required. We concluded therefore that they must have been cargo. We also discovered in the seabed two marble discs, which we guessed were the ship’s eyes. It has long been known from vase paintings that classical Greek ships—like those from other cultures—had eyes to give them life or help them see their way through the waves. Although warships were known to have had naturalistic marble eyes attached to them, most scholars assumed that the eyes on more modest merchant ships were depicted as simple circles painted onto the sides of the vessel.
Did the sailors who depended on these eyes for safety survive the ship’s last voyage They could have lived through the actual sinking. The ship was less than a hundred yards from land when it sank, so they might have swum towards the shore. And we know from Greek literature that some ships had lifeboats. But proximity to land and having lifeboats are no guarantee of safety. Even if some had swum to shore, it’s hard to imagine that many managed to crawl up on the exposed and sharp rocks while being smashed by waves like those that almost certainly sank their ship.

What point does the writer make about the exploration in the first paragraph ______

A. It was most effective when carried out by a small team.
B. It required each diver to possess a variety of skills.
C. It had to take into account risks to the divers.
D. It had been made easier by technological developments.
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