【单选题】已知平面向量 的夹角为 ,且 ,在△ABC中, ,D为BC中点,则 等于( )
【多选题】某日夜,郑某驾驶东风卡车正常行驶,通过某交叉路口时,发现赵某驾驶摩托车闯红灯,遂紧急制动,赵某驾车撞上东风卡车,经抢救无效死亡经查,赵某系酒后无证驾驶某县公安局交警大队认定赵某负全部责任赵某的妻子杨某不服,认为郑某将人撞死,应承担交通事故主要责任,多次到交警大队办公场所吵闹,严重影响办公秩序一日,杨某将赵某的尸体抬至交警大队门口,要求交警大队重新作出交通事故认定,经处警民警教育劝阻,仍不同意将尸体...
A.
杨某实施的两种违法行为均属于妨害社会管理行为
B.
杨某实施了阻碍人民警察依法执行公务的违法行为
C.
杨某违反了两种违反治安管理行为,应当分别决定,合并执行
D.
如对杨某决定行政拘留处罚,合并执行最长不超过二十日
【单选题】It is true that ______.
A.
the average man often uses in his own vocabulary what was once technical language not meant for him
B.
various professions and occupations often interchange their dialects and jargons
C.
there is always a clear-cut nontechnical word that may be substituted for the technical word
D.
an educated person would be expected to know most technical terms
【单选题】如图蜘蛛在地面于竖直墙壁间结网,蛛丝AB与水平地面之间的夹角为450,A到地面的距离为1m,已知重力加速度9取10m/s2,空气阻力不计,若蜘蛛从竖直墙上距地面0.8m的C点以水平速度υo。跳出,要到达蛛丝,水平速度υo。可以为( )。
【单选题】已知平面向量 a , b 的夹角为 π 6 ,且 a ? b =3,| a |=3,则| b |等于( )
【单选题】4-32. --- Does Jimmy always go to school by bus? --- No, rather than __________ on a crowded bus, he always prefers __________ a bike.
【简答题】已知一圆锥面的顶点为S,轴线L与母线的夹角为30°,在轴线L上取一点C,使SC=4,过点C作一平面与轴线的夹角等于60°,则与截平面相切的两个焦球中较小一个球的半径为 .