如果一束来自远处的光眼睛的角膜和晶状体折射后所成的像落在视网膜(选填“前”或“后

题型:填空题

问题:

如果一束来自远处的光眼睛的角膜和晶状体折射后所成的像落在视网膜(选填“前”或“后”)______,这就是近视眼,矫正的方法是戴一副由凹透镜片做的眼镜.矫正前像离视网膜越远,所配眼镜的“度数”越______.(选填“深”或“浅”).

考点:近视眼及其矫正
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第二次世界大战以前,非洲三个独立的国家是(  )

A.利比亚、埃及、埃塞俄比亚

B.利比亚、埃及、坦桑尼亚

C.利比里亚、埃及、埃塞俄比亚

D.利比亚、尼日利亚、埃及

题型:填空题

婴儿痉挛症首选()

A.利他林(哌甲酯)

B.地西泮

C.泰比利

D.ACTH

E.丙戊酸钠

题型:填空题

读下图回答下列问题。

小题1:下列关于二氧化碳排放叙述正确的是

A.中国二氧化碳排放总量最大是经济发展速度过快造成的

B.印度城市人口比重过高,汽车数量过多造成二氧化碳排放量大

C.美国二氧化碳排放量最大的原因主要是能源消耗量大

D.造成俄罗斯与日本二氧化碳排放量接近的原因相同小题2:二氧化碳排放过多会导致气候变暖的原因是

①大气吸收太阳辐射增强 ②大气吸收地面辐射增强

③大气反射地面辐射增强 ④大气逆辐射增强

A.①②

B.②③

C.①③

D.②④小题3:人均碳排放量最大的国家早期经济发展,以污染环境来获取高利润的做法违背了可持续发展的

A.公平性原则

B.持续性原则

C.共同性原则

D.阶段性原则

题型:填空题

Tail Spin

Two dolphins race around in a big pool in the Ocean Park. The smaller dolphin Grace, shown off a few of her tricks, turning around and waving hello to the crowd. The most amazing thing about her, however, is that she’s even swimming at all. She doesn’t have a tail.

Grace lost her tail as a baby when she got caught up in a fish trap.

When the dolphin arrived at the Ocean Park in December 2005, she was fighting for her life. “Is she going to make it?” Her trainer, Abbey Stone, feared the worst. Grace did make it — but her tail didn’t. She ended up losing her flukes and the lower part of her peduncle.

Over the past six years, she has learned to swim without her tail. Dolphins swim by moving their flukes and peduncle up and down. Grace taught herself to move another way—like a fish! She pushed herself forward through the water by moving her peduncles from side to side.

The movement put harmful pressure on Grace’s backbone. So a company offered to create a man-made tail for her. The tail had to be strong enough to stay on Grace as she swam but soft enough that it wouldn’t hurt her.

The first time Grace wore the artificial tail. She soon shook it off and let it sink in the bottom of the pool. Now, she is still learning to use the tail. Some days she wears it for an hour at a time, others not at all. “The tail isn’t necessary for her to feel comfortable,” says Stone, “but it helps to keep that range of motion(动作) and build muscles(肌肉).”

Now, the dolphin is about to get an even happier ending. This month, Grace will star in Dolphin Tale, a film that focus on her rescue and recovery. Her progress has inspired more than just a new movie. Many people travel from near and far to meet her. Seeing Grace swim with her man-made tail gives people so much courage.

小题1:When Grace first arrived at the Ocean Park, her trainer worried about her .

A.physical build

B.potential ability

C.chance of survival

D.adaptation to the surroundings.小题2:A man-made tail is created for Grace to     .

A.let her recover faster

B.make her comfortable

C.adjust her way of swimming

D.help her perform better tricks小题3:The story of Grace inspires people to   .

A.stick to their dreams

B.treat animals friendly

C.treasure what they have

D.face difficulties bravely

题型:填空题

汽轮机停机以后的快速强制冷却根据冷却介质不同分为()冷却和()冷却。

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