【判断题】电阻焊设备采用的加热原理为电阻加热原理。
【简答题】如图电路中,电阻R L 可变,其余参数为定值,试问,R L =?P L 为最大,且P Imax =?(R L ≠r m )
【单选题】I am interested _____ football, but I am not good _____ it. [ ]
【多选题】RH为( ),RM为( ),RL为( )。
【单选题】Not only ______ in photography, but _____ an courses to update my skills.
A.
I am interested; I took
B.
interested I am; did I take
C.
I am interested; did I take
D.
am I interested; I took