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问题 选择题
双曲线
x2
5
-
y2
4
=1的离心率e等于（　　）
A．
5
5
B．
2
5
C．
3
2
D．
3
5
5
答案

∵双曲线方程为

x2
5
-
y2
4
=1

∴a2=5，b2=4，可得a=

5
，b=2且c=
a2+b2
=3

因此，该双曲线的离心率e=

c
a
=
3
5
=
3
5
5

故选：D

单项选择题

A new mother is concerned because her breast-feeding neonate wants to "nurse all the time. " Which of the following responses best indicates the normal neonate’s breast-feeding behavior

A. "Breast milk is ideal for your baby, so his stomach will digest it quickly, requiring more feedings. "
B. "Let me call the lactation consultant to make sure that your baby is feeding properly. "
C. "Don’t worry; your baby is an aggressive feeder and needs a lot of sucking satisfaction. "
D. "It seems as if your baby is hungry. Why don’t you provide your baby with some formula after the feeding to make sure he’s getting enough nourishment"
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单项选择题

办理变更车身、车架业务时应由（）受理。

A.登记审核岗

B.牌证管理岗

C.查验岗

D.档案管理岗
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