I was looking for a birthday gift for my mother, but I couldn't find ______ suitable.
A:something
B:anything
C:nothing
D:everything
关于电流、电压和电阻的关系,下列说法中正确的是( )
海水是巨大的资源宝库.如图所示利用海水为原料可获得许多化工产品: