使用逐差法的条件是：自变量是严格（）变化的，对一次逐差必须是_爱下问搜题

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问题填空题

使用逐差法的条件是：自变量是严格（）变化的，对一次逐差必须是（）关系。

答案

参考答案：等间距；线性

解答题

甲乙两个工程队合建一座大楼，甲队的工作效率是乙队的

，两队合建10周正好完成这座大楼的

，余下的工作由甲队单独做，还要多少周才能建完？

完形填空

完形填空（共20小题；每小题2分，满分40分）
阅读下面短文，掌握其大意，然后从1-20各题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。
The trip to that city was eye-opening for everyone，and near its end，all the young people in our group began to reflect on what it had meant. We _1__the first night we had arrived. We had all gone into the markets of the city __2_the young people could experience its energy. But what we actually saw simply __3_ us all—the rundown houses，the children in rags，the people begging for money...Walking home，__4under a low bridge，we came across __5__families of homeless people seeking a bit of dry ground to sleep on __6_the night. We had to step over bodies as we found our way through the darkness.
The poverty(贫困) was __7_than anything my young companions had ever imagined. Back in the hotel，an air of sadness settled over the group. Many _8__ and cried. Spending time in this 9_ moves a person to care about humanity.
That evening，our group spent hours talking about what we had _10_.Gently，I encouraged everyone to talk about the difficult _11__ that day’s discoveries had inspired. Sitting together __12_ a circle as everyone had a chance to speak，we all began to realize that __13__ of us was alone in our struggle to cope with our reactions.
Based on my __14__in poverty-stricken areas，I suggested that __15_ the emotions we had were painful，they could also be important in helping us to move forward. We all__16_ that we had seen things that should never be allowed to happen._17__，what could we do about it？Together，we began to brainstorm ways we could help to ease the __18__ we had seen. As I encouraged group members to focus on __19__ they could do，a sense of determination __20__ the previous sadness. Instead of despair，these young people began to feel a call to action.

A．put up with

B．got back to

C．made up for

D．looked back on

C．embarrassed

D．environment

D．impressions

A．experiences