（I）设f（x）的导函数为g（x），求g（x）在区间0，l上的最小值；

（II）若f（1）=0，且函数f（x）在区间（0，1）内有零点，证明：﹣1＜a＜2﹣e．

设$z=x+y$，其中$x,y$满足$\left\{\begin{array}{c}x+2y\ge 0\\ x-y\le 0\\ 0\le y\le k\end{array}\begin{array}{c}\\ \end{array}\right.$，若z的最大值为6，则z的最小值为    (    )

已知$x_1,x_2$是函数$f\left(x\right)={\left(\frac{x}{x-2}\right)}^2-\frac{4x}{x-2}+1$的两个零点，则$x_1+x_2=( \; )$

根据材料内容，选择正确答案。

Hi Eric,

    We don't have smog in Oxford. We get fog sometimes, but that's all. Oxford is much smaller than L.A. We only have about 135,000 people. I looked up the 1900 population, it was about 57,000. So it is about twice as many people, not ten times as many, like L.A.! Oxford is much smaller than London—London has about 7,000,000 people. So that means that L.A. has more people than London. L.A. gets hotter than Oxford. We have colder winters too—it can be -4°C in winter.

    I'm not surprised that your new student only knew about the university. It is famous because it is one of the oldest universities in the country. There are about 18,000 students. The brother of my best friend is at Aberystwyth University, in Wales. There the population is 14,000 and half of that are students! It must be a strange place to live! There are more tourists in Oxford than students, I should think. We get a lot of tourists, all year round. We also get a lot of young foreign students because there are a lot of language schools here. You can stand in the middle of Oxford, close your eyes, and hear accents from all over the world!

                                                 Your e-mail friend,

                                                        Ben