某同学有一段导体,他为了使导体的电阻减小,下列采用的方法中正确的是 [ ]
A.截短导体的长度
B.增大导体的长度
C.增大通过导体的电流
D.减小加在导体两端的电压
答案:A
Britain is _____ France by the English Channel, and the whole Britain is _____ three parts. [ ]
A. divided into; separated from
B. separated from; divided into
C. divided into; divided into
D. separated from; separated from
海关是国家的监督管理机关,实施监督管理的范围是进出国境的活动。 ( )