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问题 填空题

设物体在8∶00到16∶00之间的温度T是时间t的函数：T(t)=at2+bt+c(a≠0)，其中温度的单位是°C，时间的单位是小时，t=0表示12∶00，t取正值表示12∶00以后，若测得该物体在8∶00的温度为8°C，12∶00的温度为60°C，13∶00的温度为58°C，则T(t)=（    ）。

答案

-3t2+t+60

改错题

短文改错

文章共有10处错误。每句最多两处。多者从第11处起不计分。

1. 增加：缺词处加∧，并在下面写出该词。

2. 删除：多余的词用╲划掉。

3. 修改：错词下面划一横线，并在下面写出修改后的词。

注意：1.每处错误及其修改均仅限一次；

2.只允许修改10处，多者（从第11处起）不计分。

Li Ming is a student who have been living in Shanghai since he was born．But his grandfather lives in Taiwan, because he went to Taiwan after Shanghai was liberated．He is a merchant．For about half a century, Li Ming’s family have no idea where she lives．They miss him very much．Fortunate, a letter from his grandfather reached them this October, which said that his grandfather would be back Shanghai on December 24th．Li Ming’s parents were such excited about the news that they didn’t sleep well for several nights．So did Li Ming．The day finally came．In December 24th, the family of Li Ming are on their way to the airport．When they met at the last, they gave his grandfather a big hug, tears in their eyes．They got together．
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选择题

“第二亚欧大陆桥”经过我国的铁路线是[ ]

A、京哈线

B、南昆线

C、陇海—兰新线

D、京九线
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