【简答题】我们知道,当一条直线与一个圆有两个公共点时,称这条直线与这个圆相交,类似地,我们定义:当一条直线与一个正方形有两个公共点时,称这条直线与这个正方形相交。如图,在平面直角坐标系中,正方形OABC的顶点为O(0,0)、A(1,0)、B(1,1)、C(0,1)。 (1)判断直线y= x+ 与正方形OABC是否相交,并说明理由; (2)设d是点O到直线y=- x+b的距离,若直线y=- x+b与正方形OA...
【简答题】天坛神乐署正殿名称是什么?其作用是什么?初建时为何名?屋顶为何形制?殿内悬有乾隆皇帝御笔书匾,其内容是什么?
【单选题】. Jack used to work in a garage for a full 10 years, so he fixed the broken engine ______ ease.
【单选题】Main propulsion engine lube oil sumps should be constructed _____.
A.
so as to never be integral lube
C.
only of nonferrous, noncorrosive metals
D.
with drain/return lines terminating just above or at the designed normal level
【简答题】以圆锥曲线的焦点弦AB为直径作圆,与相应准线 有两个不同的交点,求证: ①这圆锥曲线一定是双曲线; ②对于同一双曲线, 截得圆为定值.
【单选题】The famous nitro boosts are added to the engine so that______ .
A.
drivers can beat other racers in speed
B.
it is smoother to start the car
C.
the car can climb the steep slope easily
D.
the car can cover a longer distance
【单选题】根据消费税法律制度的规定,委托加工的应税消费品在( )征收消费税。
【单选题】在 Word中,正文首行缩进(符合中文段落常规格式),正确的操作应该是: