在$△ABC$中,角$A,B,C$所对的边分别为$a,b,c$,且满足$a\sin B=b\cos A$,则$\sqrt{2}\sin B-\cos C$的最大值是(    ) 

其中a_k=（k=0，1，2，3，4）等于在a₀，a₁，a₂，a₃中k所出现的次数．

则a₄=____； a₀+a₁+a₂+a₃=____．

The tall building          here for 100 years.

    Miss White is in Beijing on vacation. Here is her hotel card. Have a look at it and answer the questions.

She _______ got long black hair. （  ）