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问题 选择题

下列反射属于复杂反射的是[ ]

A．下落的灰尘引起的眨眼      

B．看见酸杏引起唾液分泌

C．婴儿吃奶时的动作        

D．针刺上肢引起的缩手

答案

答案：B

完形填空
The students’ vacation plan
Who
What
When
How long
Hector
going to the summer camp
this Sunday
1 day
Susan
going to the beach
on Friday
2 days
Molly
going to Beijing
October 1
3 days
Rick
visiting cousins
The first week in September
7days
Information Card
Who to go to the summer camp
小题1:_______________.
Time for Susan to go to the beach
小题2:___ _______________________.
Things Rick is going to do for vacation
小题3:_______________________.
How long for Molly to stay in Beijing
小题4:__________________________.
Time for Rick to visit his cousins
小题5:_______________________.
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不定项选择

设土星绕太阳的运动为匀速圆周运动，若测得土星到太阳的距离为R，土星绕太阳运动的周期为T，万有引力常量G已知，根据这些数据，能够求出的量有[ ]

A．土星线速度的大小

B．土星加速度的大小

C．土星的质量

D．太阳的质量

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