Tom ____ (not go) to school on weekends.
Who was ____ (four) in the race?
如图所示,理想变压器的原线圈接u=11000 2 sin100πt(V)的交变电压,副线圈通过电阻r=6Ω的导线对“220V/880W”的电器RL供电,该电器正常工作.由此可知( )
图中A所在地区主要农作物及其熟制的说法,正确的是( )