单选题设，则f"(x0)=______。

单选题设f(x)为连续函数，

单选题已知某厂每天生产z千克产品的总成本为(元)，要使产品的平均成本最小，每天应生产该产品( )． A．132千克 B 140千克 C．150千克 D．156千克 E．160千克

单选题行列式|D|非零的充分条件是( )。 (A) D的所有元素非零 (B) D至少有n个元素非零 (C) D的任意两行元素之间不成比例 (D) 以D为系数行列式的齐次线性方程组有唯一解

单选题German Chancellor Angela Merkel won over German voters in the Federal Election on Sept. 27. Can she now be won over by a French charm offensive (1) at repairing the relationship that was once at the heart of Europe? That's the question being asked in Paris, (2) top government officials are (3) talking about their desire to rekindle closer ties (4) their neighbors across the Rhine. (5) the end of World War II the Franco-German relationship has been the motor of European integration, the (6) force behind the creation of the European Union and, more recently, the introduction of the euro. But the ardor has (7) in this decade, particularly under Merkel, who has regularly struggled to (8) her irritation with French President Nicolas Sarkozy's grandstanding. Sarkozy, (9) , has often been impatient with what he (10) Merkel's lack of resolve. The sometimes (11) personal rapport is a long way from the public shows of affection their predecessors staged, particularly Helmut Kohl and FranCois Mitterrand, who movingly held (12) in 1984 in a Verdun cemetery. There's been tension on (13) , too. Charles Grant, director of the London-based think tank Centre for European Reform, points out that France and Germany have been (14) on issues from how best to reflate their economies during the economic (15) to the smartest strategies for dealing with Russia. But influential movers in France are now (16) to put the relationship back on a friendlier footing. In a recent paper French think tank Institute Montaigne (17) an ambitious agenda for the two nations, (18) that a new impetus is needed if Europe's voice is to be heard in a world (19) of big new players, such as Brazil and India, and at a time when President Obama seems fax more (20) with China and the rest of Asia than with America's traditional allies in Europe.

单选题公有制为主体、多种所有制经济共同发展，是我国社会主义初级阶段的一项基本经济制度。决定实行这一制度的理论依据是______。 A．生产力发展和生产关系性质 B．发展市场经济和扩大对外开放 C．社会主义性质和初级阶段国情 D．所有制结构和分配结构

单选题快慢两列火车长度分别为160米和120米，它们相向行驶在乎行轨道上，若坐在慢车上的人见整列快车行驶过的时间是4秒，那么坐在快车上的人见整列慢车驶过的时间是( )秒．

单选题设，则A.x=0与x=1都是f(x)的第一类间断点．B.x=0与x=1都是f(x)的第二类间断点．C.x=0是f(x)的第一类间断点，x=1是f(x)的第二类间断点．D.x=0是f(x)的第二类间断点，x=1是f(x)的第一类间断点．

单选题设D为有界闭区域，z=f(x，y)在D上二阶连续可偏导，且在区域D内满足：则______．

单选题设，则有______

单选题等于______A．arcsinxB．C．arcsinb-arcsinaD．0

单选题设条件收敛，且，则______．

单选题设ƒ（x+1）=x（x+1），则ƒ（2）=（　）

单选题3个男生与2个女生站成一排，要求女生不能相邻，不同方法数有( )．

单选题某条路上有4个旅馆，现有有6名旅客，每一位旅客投宿每个旅馆都是等可能的，则这6名旅客投宿4个旅馆的人数恰好为2，2，1，1的概率为()．

单选题买卖兵器，珍异等小件物品使用的较短契券称为( )。 A．傅 B．别 C．质 D．剂

单选题The border incident led to the two countries ______ diplomatic relations. A. breaking off B. breaking up C. cutting off D. cutting up

单选题设函数f(x)在x=1处可导，且f"(1)=2，则=______A．-2B．C．D．2

单选题下列极限正确的是______。A．B．C．D．

单选题有5名外国运动员，4名中国运动员参加跳水奥运会比赛，则恰有两名中国运动员接连出场的比赛顺序共有( )种．