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问题 选择题

函数f(x)=x2+2(a-1)x+2在区间(-∞，4］上递减，则a的取值范围是 [ ]

A、[-3，+∞)

B、(-∞，-3]

C、(-∞，5]

D、[3，+∞)

答案

答案：B

完形填空

More and more families go on a car trip each year. However, the thought of trouble on the road may p小题1:   you from going out. To a 小题2:  trouble, you need to make a careful plan for your trip.

First of all, choose a proper route for your trip. Consider w 小题3:  you are going and find several possible routes to it. Traffic and the t 小题4:  that you will spend on the road must be considered when you decide one.

Consider your luggage(行李) needs. B 小题5:  you begin packing your necessities(必需品), think about how many people will be in your car and how much space they will need in order to t  小题6:  comfortably.

Try to miss busy times. Usually highways are b 小题7:  on Fridays and Sundays, so you’d better go on Tuesdays or Thursdays. Driving at night is also a great way to miss the traffic and the kids can sleep d 小题8:  the trip.

F 小题9:  , do not forget to check your car carefully before leaving so that you can have as 小题10:  trip.
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单项选择题

哪种食物中的铁容易被人体吸收

A．菠菜
B．牛奶
C．水果
D．动物性食品
E．糕点
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