单选题当n≥2时，计算n阶行列式的值为______。A．-2(n-2)!B．(n-2)!C．2(n-2)!D．4(n-2)!

单选题一组数据有10个，数据与它们的平均数的差依次为-2，4，-4，5，-1，-2，0，2，3，-5，则这组数据的方差为______．

单选题设周期函数f(x)在(-∞，+∞)内可导，周期为4，又，则曲线y=f(x)在点(5，f(5))处的切线斜率为______。A．B．C．-1D．-2

单选题女口果0＜p＜15，那么代数式|x-p|+|x-15|+|x-p-15|在p≤x≤15的最小值是( )。 (A)30 (B)0 (C)15 (D)p-15 (E)一个与p有关的代数式

单选题[2009年10月]一个球从100米高处自由落下，每次着地后又跳回前一次高度的一半再落下。当它第10次着地时，共经过的路程是( )(精确到1米且不计任何阻力)。

单选题某班同学在一次测验中，平均成绩为75分，其中男同学人数比女同学多80%，而女同学平均成绩比男同学高20%，则女同学的平均成绩为______．

单选题设u=f(x，xy，xyz)，则=______．

单选题两地相距351千米，汽车已行驶了全程的，试问再行驶多少千米，剩下的路程是已行驶的路程的5倍?答案是()千米．(A)19.5(B)21(C)21.5(D)22(E)A、B、C、D都不正确

单选题如图6—23，等腰直角三角形的面积是12cm2，以直角边为直径画圆，则阴影部分的面积是()cm2．

单选题，变换积分次序为______A．B．C．D．

单选题设b≠0，当x→0时，sinbx是x 2 的______

单选题Narrative crept back into art through a side door marked fashion photography. In April 1967, French Vogue published a spread by Bob Richardson, the American photographer, that soon became a legend Informally christened " the Greek trip " by Richardson's admirers, the spread featured Donna Mitchell, a striking brunet model, hanging out on the Aegean island of Rhodes with a male companion. Of course, narrative never disappeared—it just went to the movies, and stayed, and stayed. But what had caused stories to be exiled from high art? The idea of essence, and the equation of essence with goodness. Can you imagine? Visual art is essentially composed of form, color, materials. Anything to do with content is extraneous and therefore to be associated with badness; therefore to be eliminated. Moreover, content, says this line of thought, is controlling. This means that a rose is the Virgin Mary (depending on what the meaning of " is " is). And art, like society, must be liberated from such hierarchically imposed values. What this argument overlooked, of course, is that narrative is a form in itself, not just a vehicle for content. Indeed, the ideology of formalism originated, in Soviet Russia, with the analysis of old folk tales. Narrative form, the analysis went, typically proceeds from an initial state of equilibrium through a series of destabilizing episodes, concluding with a heightened state of equilibrium at the end. Think Indiana Jones. You can plug whatever content you want in there as long as it creates the form. Each episode simply has to do with the work of creating disequilibrium. A narrative does not, in other words, tell a story. A story is told to give listeners the pleasure of the narrative form. If you were to isolate the form of disequilibrium from the specifics of plot, you might arrive at something resembling the collected work of Cindy Sherman. Initially modeled after movie stills, Sherman's pictures are not, of course, abstract. Over the years, in fact, their content has become increasingly elaborate. I see this as a form of generosity as well as a sign of advanced technical skills. Not since Giuseppe Arcimboldo (1527-1593), perhaps, has an artist contrived to turn the human figure into a more bountiful cornucopia for the eye. Yet even the most visually splendid of Sherman's images are minimalist, in that they reduce the narrative down to the precise moment when the center of gravity shifts. Perhaps some unheard word is spoken. A floorboard squeaks. From upstairs comes a thump. And a tentative state of equilibrium gives way to anxiety or dread. That moment, too, represents essence. What more do you need to know?

单选题数列极限=______A．0．B．1．C．∞．D．

单选题计算二重积分，其中D=．