12×2=1 故12的倒数为2
2÷5=25=0.4×100%=40%
故填:40.
–What took you so long? –I got lost. I have no sense of direction.
A.sense
B.ability
C.knowledge
D.feeling
下列不属于燃烧的基本形式的是:()
A、自燃
B、爆炸
C、热辐射
D、以上均不是