在二次函数y=-x2+bx+c中，函数y与自变量x的部分对应值如下表：
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∵x=-2时，y=-7，x=4时，y=-7，
∴抛物线对称轴为直线x=
=1，即（1，2）为抛物线的顶点，-2+4 2
∴2为抛物线的最大值，即抛物线开口向下，
∴当x＞1时，抛物线为减函数，x＜1时，抛物线为增函数，
∴（2，m）与（3，n）在抛物线对称轴右侧，且2＜3，
则m＞n．
故选A．
We arrived in Spain for the _36_ time a few weeks ago and I decided to buy a car because we had sold _37_ we had in England before leaving. Yesterday the _38_ office rang us to tell the car was ready. I had _39_ out a model like it before but as I was not yet used to _40_ in this city, my wife did not want me to collect it on my own, so we went _41_ to fetch it. We paid for the car and _42_ the papers. They told us there was enough _43_ to take us to a garage, where we could fill up. (加油)The nearest garage to the _44_ was about 100 yards away and we got there _45_ .But when I turned into the main road I suddenly saw a lot of _46_ racing towards me .I got out of their way as _47_as I could by backing into the garage once more and the man behind _48_ at me . “It’s such a _49_ to remember to drive on the right, isn’t it?” My wife said.“Yes, if only I had _50_ a few lessons for practice,” I replied . “You’d better go carefully on the way_51_ ,” my wife said. “You ’d be _52_ if you had an accident _53_ the first day, wouldn’t you ?” While we were talking, the man behind _54_ out of his car and said in good English, “Would you mind telling me when you are thinking of leaving , _55_ are you going to sit in your car all the day?”
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