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读图回答1～2题

1．H经线穿越的我国大地形区有 [     ]

A．内蒙古高原、黄土高原、青藏高原、云贵高原

B．内蒙古高原、黄土高原、四川盆地、云贵高原

C．黄土高原、长江中下游平原、四川盆地、云贵高原

D．准噶尔盆地、天山、塔里木盆地、青藏高原

2．E纬线穿过的我国省级行政单位有[     ]

A．山东省、河北省、山西省、甘肃省、新疆维吾尔自治区

B．河北省、山西省、内蒙古自治区、甘肃省、青海省

C．辽宁省、河北省、山西省、甘肃省、新疆维吾尔自治区

D．江苏省、河南省、陕西省、宁夏回族自治区、青海省

答案

1．B

2．C

判断题

汽车发动机中，润滑油有起密封作用的情况。
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单项选择题

Some spiders hunt on the ground, others build webs to trap their food, but the grass water spider catches its prey by running along the surface of the water.
This special water spider lives on the grassy banks of streams where mosquitoes, damsel flies and other insects come to feed and breed.
Although it is one of the largest spiders in New Zealand, it has an unusual ability. It doesn’t disturb the water as it waits for its meal, and there is barely a ripple when it skims across the surface at lightning speed to catch its prey.
Grass water spiders deal swiftly with larger insects like damsel flies by pulling their heads under the water and holding them there until they drown.
After a meal, the grass water spider spends up to half an hour grooming itself. It wipes its eight eyes, brushes its antennae, and takes special care to clean the hairs on its body.
It is the hairs that trap tiny bubbles of air so that the spider can run down a blade of grass and stay underwater for up to an hour when it is frightened. The hairs also keep the spider dry, even underwater.
It is only when the female spider is caring for the young that she does not hunt on the water. After mating, she produces a large egg sac, which she carries around for five weeks. Once the eggs start to hatch, she attaches the sac to some blades of grass or a thistle. She then tears the sac open and releases the tiny spiders into the nursery web.

How does the grass water spider kill its prey

A. In a web



B. By drowning
C. By poisoning


D. With its antennae
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