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问题 不定项选择

如图所示，图中a、b、c、d四条圆轨道的圆心均在地球的自转轴上（其中轨道a与赤道共面，轨道b、c的圆心与地心重合），则下列说法正确的是

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A.卫星可能在轨道a上绕地球做匀速圆周运动且与地球表面相对静止

B.卫星不可能在轨道b上绕地球做匀速圆周运动

C.同步卫星的轨道可以是轨道d

D.若圆轨道a、c的半径Ra=Rc，则在轨道a和轨道c上绕地球做匀速圆周运动的卫星的周期Ta=Tc

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单项选择题 B型题

行产钳术时未行适度的会阴切开可导致（）

A.会阴Ⅲ度裂伤

B.宫颈裂伤

C.胎盘滞留

D.胎膜残留

E.胎盘小叶缺损
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单项选择题

I shouldn’t let it bother me. It really doesn’t matter anyway. But it does bother me ! All those people are preparing to (21) a new century, a new millennium (千年) as well. And it just isn’t (22) !
Most of us schedule our lives by the Gregorian (23) . Our years are measured from the (24) of Christ. The first year of the first century is 1, or 1 A.D. The last year of that century is the year 100. Simple Yes! A century is 100 (25) long. A millennium is 1,000 years long, which is (26) ten centuries.
Since the last year of the first century is the year 100, the first year of the (27) century is 101. Follow that pattern, century by century and you’ll get my (28) . The year 2000 is the last year of the twentieth century. After all, (29) thousand means twenty hundreds. Twenty hundred years means twenty centuries. The year 2000 is the (30) , the final, the one that’s still here, year of the twentieth century!!!!
I know, I’m getting too (31) . But it isn’t fair, While most people will really be enjoying this coming (32) celebration, those of us in the know will be yawning. Everyone else will be (33) for the new millennium and we’ll be saying, "It’s not until next year."
I don’t agree with the (34) , "Ignorance is bliss." But in this case, perhaps it’s (35) .

A．a

B．seven

C．two

D．which
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