下列说法正确的是( )
A:该电池常温下可稳定工作
B:放电时,电能转变为化学能
C:充电时,阳极发生反应:4OH--4e-=2H2O + O2↑
D:放电时,负极室发生反应:Fe + xH2O(g) △__ FeOX+xH2,负极发生反应:H2+O2--2e-=H2O
— Jack, I call to tell you I have no time to attend your party next Friday. —What a pity!
若{an}为等差数列,Sn是其前n项和,且S11= 113 π,{bn}为等比数列,b5•b7= π24 ,则tan(a6+b6)的值为 ( )
一个两位数N具有性质:N与颠倒N的数字后的数之和为完全平方数,则这样的N有____ 个.
Will they go dancing next Sunday? (否定回答)
____, they____.