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【单选题】
An even more exciting find was reported in 1994, also from Pakistan. The now extinct whale Ambulocetus natans ("the walking whale that swam") lived in the Tethys Sea 49 million years ago. It lived around 3 million years after Pakicetus but 9 million years before Basilosaurus. The fossil luckily includes a good portion of the hind legs. The legs were strong and ended in long feet very much like those of a modern pinniped. The legs were certainly functional both on land and at sea. The whale retained a tail and lacked a fluke, the major means of locomotion in modern cetaceans. The structure of the backbone shows, however, that Ambulocetus swam like modern whales by moving the rear portion of its body up and down, even though a fluke was missing. The large hind legs were used for propulsion in water. On land, where it probably bred and gave birth, Ambulocetus may have moved around very much like a modern sea lion. It was undoubtedly a whale that linked life on land with life at sea. Why does the author use the word "luckily" in mentioning that the Ambulocetus natans fossil included hind legs?
A.
Fossil legs of early whales are a rare find.
B.
The legs provided important information about the evolution of cetaceans.
C.
The discovery allowed scientists to reconstruct a complete skeleton of the whale.
D.
Until that time, only the front legs of early whales had been discovered.
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【简答题】已知不等式ax ;当a(    )时,不等式的解集为x> 。
【单选题】根据下列表格对应值: x 3.24 3.25 3.26 ax 2 +bx+c -0.02 0.01 0.03 判断关于x的方程ax 2 +bx+c=0的一个解x的范围是( )
A.
x <3.24
B.
3.24 <x<3.25
C.
3.25 <x<3.26
D.
3.25 <x<3.28
【单选题】This news report mainly talks about ______.
A.
how Beijing is becoming a 21st-century city
B.
how many projects are being dealt with to improve the traffic of Beijing
C.
how Beijing is being built into a first-class Olympic host city
D.
the use of the 20 billion dollars
【单选题】监理人员在施工现场辦工程实体关键部位或关键工序的施工质量进行的监督检查 活动称为( )o
A.
检验
B.
平行检验
C.
D.
【单选题】三极管的特性曲线是表示三极管各极电流与极间电压之间的关系曲线,主要有( )。
A.
输入特性曲线
B.
输出特性曲线
C.
输入特性曲线和输出特性曲线
D.
交直流负载线
【简答题】已知计算公式 (其中A=3.24,B=8.5,C=10.003)
【单选题】根据下列表格的对应值:判断方程ax 2 +bx+c=0(a≠0,a、b、c为常数) 一个解的范围是 [     ]
A.
3<x<3.23
B.
3.23<x<3.24
C.
3.24<x<3.25
D.
3.25<x<3.26
【简答题】24 已知(AX)=77FFH,(CX)=305H,执行指令: SHL AX,CL PUSH CX MOV CL,CH RCL AX,CH POP CX AND CL,CH RCR AX, CL 后,(AX)= ,(CF)= 。
【单选题】压疮淤血红润期的主要护理措施是
A.
除去病因,定时翻身
B.
局部使用抗生素,避免感染
C.
厚层滑石粉包扎,减少摩擦
D.
清洁创面,除腐生新
E.
红外线照射,干燥创面
【单选题】已知等式(ax 2 +bx-5)(ax 2 +bx+25)+c=(ax 2 +bx+10) 2 ,那么c的值为(  )
A.
5
B.
25
C.
125
D.
225
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