一次函数y=kx+b的图象如图所示,则k、b的值为( )
A:k>0,b>0
B:k>0,b<0
C:k<0,b>0
D:k<0,b<0
As students, _______, we should study hard to be well prepared for the future.
下列句子中划线的成语使用不正确的一项是:( )
如图1所示,已知小灯泡L上标有“6V 3W”字样,R0=20Ω,滑动变阻器R的最大阻值为100Ω。求: