下图是血液循环过程中某段示意图(箭头表示血流方向)，如果图中b为心脏的左心房和左心室，则血管c的名称是 A．主动脉B．肺动脉C．肺静脉D．
生活中许多实例应用到物理知识.下列说法错误的是( )A．用吸管从瓶中吸饮料——液压技术B．用重垂线来检查墙壁上的画是否挂正——重力方向竖
__ helped a lot in our country. A.The blind is B.The blind are C.The blinds is D.Blind are
Cold weather can be hard on pets, just like it can be hard on people. Sometimes owners forget that their cats are just as used to the warm shelter (住所) as they are. Some owners will leave the
已知函数f(x)=2x-1的反函数为f-1(x)，g(x)=log4(3x+1)(1)用定义证明f-1(x)在定义域上的单调性；(2)若f-1(x)≤g(x)，求x的取值集合D；(3)设函数H(x)=g(x)-f-1(x)，当x∈D
According to the rules, students must not ____ their books during examinations. A. read B. watch C. notice D. look at
5．下列文学常识和文化常识的表述，不正确的一项是（ ） A．《史记》是我国第一部纪传体通史，作者司马迁。鲁迅称其为“史家之绝唱，无韵之
在一定条件下，将A2和B2两种气体通入1 L密闭容器中，反应按下式进行：xA2+ yB2 ==2C(g)， 两秒种后反应速率如下V(A2)＝0.4mol／(L·s) V(B2)==1.2 mol／(L·s)
