问题
选择题
30．You can't expect them to______the job open for much longer— you’ll have to decide whether you want it or not．
A．take
B．hold
C．let
D．Have
答案
答案：B
搜题请搜索小程序“爱下问搜题”
30．You can't expect them to______the job open for much longer— you’ll have to decide whether you want it or not．
A．take
B．hold
C．let
D．Have
答案：B
的负电荷由a点移到b点，克服电场力做功
；再由b点移到c点，电场力对该负电荷做功为
，则a、c两点哪点电势较高？a、c两点间的电势差为多少？