【单选题】Meanwhile, the theft of information about some 40 million credit-card accounts in America, disclosed on June 17th, overshadowed a hugely important decision a day earlier by America's Federal Trade Com...
B.
It is disclosed on June 17 th .
【单选题】※水能够作为能量转换的介质,主要是因为水具有:
【单选题】※蒸汽的溶解携带能力,与蒸汽和水的密度的比有关,蒸汽和水的密度的比越小,则( )
【简答题】[理]如图,已知动点A,B分别在图中抛物线y 2 =4x及椭圆 x 2 4 + y 2 3 =1 的实线上运动,若AB ∥ x轴,点N的坐标为(1,0),则△ABN的周长l的取值范围是______. [文]点P是曲线y=x 2 -lnx上任意一点,则P到直线y=x-2的距离的最小值是______.
【简答题】曲线 ,y=lnx 及直线y=0,y=1 所围成的图形的面积 为 ;
【简答题】小题1:English is tested on_______ according to the time table A. June 15 B. June 16 C. June 17 小题2:Which of the following exams takes the longest time ? A.Chinese. B. P...
【单选题】以下三个命题:①关于x的不等式 1 x ≥1 的解为(-∞,1]②曲线y=2sin2x与直线x=0, x= 3π 4 及x轴围成的图形面积为s 1 ,曲线 y= 1 π 4- x 2 与直线x=0,x=2及x轴围成的图形面积为s 2 ,则s 1 +s 2 =2③直线x-3y=0总在函数y=lnx图象的上方其中真命题的个数是( )