下列反应属于化合反应的是（ ）
A．乙炔+氧气点燃二氧化碳+水
B．氢气+氧气点燃水
C．氧化汞△汞+氧气
D．水通电氢气+氧气
答案：B
Tom was at a loss as to how a car worked, so it was ______ that he knew nothing about how to repair cars.
A．apparent
B．absurd
C．confused
D．complicated
电脑：鼠标
A．水壶：茶杯
B．手机：短信
C．船：锚
D．录音机：磁带
