某化合物4.6g完全燃烧,生成8.8g二氧化碳和5.4g水,该化合物中 ( ) A.只含碳、氢两种元素 B.只含碳、氧两种元
若x2+y2+(λ-1)x+2λy+λ=0表示圆,则λ的取值范围是( )A.λ>0 B.≤λ≤1 C.λ>1或λ< D.λ∈R
如图,已知MB = ND,∠MBA = ∠NDC,下列条件中不能判定 △ABM≌△CDN的是( ) A. ∠M = ∠N B. AM∥CN C. AB = CD D. A
The surface of the table _____________. A. feels soft B. feels softly C. is felt soft D. is felt softly
在分层设色地形图上,平原一般用什么颜色表示( ) A.红色 B.绿色 C.蓝色 D.黄色
如图,在矩形ABCD中,AB=3,BC=4.动点P从点A出发沿AC向终点C运动,同时动点Q从点B出发沿BA向点A运动,到达A点后立刻以原来的速度沿AB返回.点P、Q运动
Need a room close to the US embassy for a week in early February I need a room close to the US embassy for a week in early February. My parents are going to the US embassy for visa interview on Febru
(04年浙江卷)椭圆的左、右焦点分别为F1、F2,线段F1F2被点(,0)分成5:3两段,则此椭圆的离心率为 (A) (B) (C) (D)