如图所示的电路中,R0是定值电阻,L是小灯泡,R是滑动变阻器,闭合开关S,发现无论怎样移动滑动变阻器的滑片,小灯泡都不发光。现用一只电压表检测这一现象产生的原因,当电压表接ab两点时,电压表无示数;接ac两点时,电压表有示数,则产生上述现象的原因可能是( )A.L短路 B.L断路 C.R断路 D.R0短路
Schools have rights to ________ their own rules based on the general conditions of the students.
[ ]
A.
make up
B.
put up
C.
set out
D.
make out