Lily, don't have ____ breakfast before the TV set. You must have meals at ____ table.
A:/, the
B:the, a
C:the, /
D:/, a
第三次科技革命的核心是( )
导体两端的电压为6V,通过它的电流是0.3A,则该导体的电阻是____ Ω;若导体两端电压变为12V,则通过它的电流为____ A;若将电路断开,该导体的电阻为____ Ω.