单选题一个等差数列的前12项的和为354，前12项中偶数项之和与奇数项之和的比是32:27，则公差d=______．

单选题设Q为三阶非零矩阵，且PQ=O，则______．

单选题一辆出租车有段时间的营运全在东西走向的一条大道上，若规定向东为正，向西为负，且知该车的行驶公里数依次为一10，+6，+5，一8，+9，一15，+12，则将最后一名乘客送到目的地时，该车的位置( )．

单选题若函数y=1-2cosx-2sin2x的值域为[a，b]，则b2+4a的值为{{U}} {{/U}}。 A.1 B.2 C.3 D.4

单选题函数y=2x的图像与直线x+3=0的交点坐标为（　）

单选题设Ω是边长为a的正方形，Ω1是以Ω四边的中点为顶点的正方形，Ω2是以Ω1四边的中点为顶点的正方形，则Ω2的面积与周长分别是()。

单选题若将10只相同的球随机放入编号为1、2、3、4的四个盒子中，则每个盒子不空的投放方法有______种．

单选题将方程去分母并化简后得到的方程是()．

单选题某商场在一次活动中规定：一次购物不超过100元时没有优惠；超过100元而没有超过200元时，按该次购物全额9折优惠；超过200元时，其中200元按9折优惠，超过200元的部分按8.5折优惠．若甲、乙在该商场购买的物品分别付费94.5元和197元，则两人购买的物品在举办活动前需要的付费总额是______元．

单选题一个圆柱的侧面展开图是正方形，那么它的侧面积是下底面积的( )倍．

单选题设函数f(x)=2x+1，x∈[0，1]，而，x∈(-∞，+∞)，其中，则______

单选题已知a=1999x+2000，b=1999x+2001，c=1999x+2002，则多项式a 2 +b 2 +c 2 -ac-bc-ab的值为______

单选题两个自然数相除所得的商为39，余数4，被除数，除数，商及余数的和等于247．除数和被除数分别为( )．

单选题若将2，4，6，8，10，12，14，16，…，依次排成一行：246810121416…，则从左向右数的第101个数码是( )．

单选题设正项级数an。发散，令Sn=a1+a2+…+an，则下列结论正确的是()

单选题设函数f(x)连续，下列变上限积分函数中，必为偶函数的是______．A．B．C．D．

单选题Judge Kleinberg got it right when he made it clear that there weren't separate rules for bloggers and journalists. That's not to say bloggers are or aren't journalists—just that there shouldn't be a distinction. In other words, the same rules apply to everyone. But—and here's the tricky part—although the rules apply to people equally, we can, do, and should apply them differently to different acts. Asking whether bloggers are journalists is meaningless. What's important isn't the person but the product. If a snoopy 12-year-old girl find evidence that her town's mayor is taking bribes, then collects it, verifies it, and publishes it on her blog, that's journalism. If Waiter Cronkite writes in his diary that he planted daisies and washed the dishes that afternoon, that's not. It's what's done, not who's doing it. This isn't something that always needed to be pointed out. In the old days, you could draw a line between journalists and everyone else, just as you could draw a line between any other profession. What you did is what you were: reporter, barber, grocer, tailor, whatever. Journalists were usually hired by newspapers, magazines and radio stations. And they followed certain rules, respecting off-the-record comments, being accurate and not misquoting. Today, the Web is an essentially way to get news, and, while journalism is pretty much the same, the term "journalist" is getting a bit cloudy. That's why the question of whether bloggers are journalists keeps coming up. When anyone can publish, anyone can be a journalist. So the questions the courts need to answer is not, "Who is a journalist?" but rather, "Who is doing journalism?" That 12-year-old girl was doing it, even if she isn't in high school yet—even if she wasn't a journalist. Not being a journalist doesn't necessarily reduce the quality of the work, nor should it reduce the protections it receives. So when a question of journalists' rights comes up, we need to ask two questions. First, "What protections should journalism receive under the First Amendment?" And second, "Was the person in question performing an act of journalism?" If she is—if the work she was doing involves gathering and publishing information of legitimate public interest—then her profession doesn't matter. The idea that the line between amateurs and professionals is blurring is something we need to get used to. The Web gives the little guy the same publishing tools as the big guy. Video-editing software is inexpensive enough that the quality of amateurs equals that of many pros. But while our technology is removing age-old distinctions, our perceptions and our laws haven't quite embraced the new reality. It's time to shift our thinking.

单选题从5张100元，3张200元，2张300元的奥运预赛门票中任取3张，则所取3张中至、少有2张价格相同的概率为()．

单选题已知，则______．A．B．C．D．E．

单选题设，则f (x )在(-1 , 1) 内