在采用国际多式联运的运输方式时,应当由()对货物的全程运输总负责
A.进口方总负责
B.出口方总负责
C.不同的承运人各自承担各自负责
D.国际多式联运的经营者总负责
参考答案:D
如下图所示,边长为l的正方形金属框abcd套在U型金属框架MNPQ内,两者都放在光滑的水平地板上,U型框架与方形金属框之间接触良好且无摩擦。方形金属框ac、bd边电阻为R,其余两边电阻不计;U型框架NQ边的电阻为R,其余两边电阻不计。虚线右侧空间存在着一个范围足够大的竖直向下的匀强磁场,磁场的磁感强度大小为B。如果将方形金属框固定不动,用力拉动U型框使它以速度v0垂直NQ边向右匀速运动,求:
小题1:拉力为多大?
小题2:bd两端的电势差为多大?
____ winter is still with us, and will be for a few more weeks, warm days may still be in the forecast for
your area. [ ]
A. As long as
B. Even though
C. Now that
D. Ever since