如图所示,A、B为咬合转动的两个齿轮,它们的半径分别为和,且则A、B两轮边缘上两点的角速度之比为= ;线速度之比= 。
由于美元持续贬值、通货膨胀率上升、全求信贷紧缩,国际投资者增持黄金,推动黄金价格上涨。2008年1月11日,金价突破每盎司900美元,黄金之所有受
The day I became a mom was not the day my daughter was born, but seven years later. Up until that day, I had been too busy trying to survive my abusive(辱骂的) marriage. I had spent all my energ
First impressions are the most lasting. After all, you never get __ second chance to make __ first impression. A. a; the B. the; the C. a; a
小明想拍一张雨后晴空的照片,小华建议他加一块滤色镜,小明应选择:A.红滤色镜; B.黄滤色镜; C.蓝滤色镜; D.绿滤色镜.
(12分)已知 (1)解关于的不等式 (2)若不等式的解集为求实数的值 .
如右图A~H都是初中化学中常见的物质, 已知A、B、C为化合物,D、E、F、G、H均为单质, 且D是目前年产量最高的金属,F为紫红色固体单质, G、H均为气
文学常识和名篇名句填空。 (1)司马迁在《屈原列传》中写道:“屈平疾王听之不聪也,__________________, , 方正之不