采用杜比降噪系统降噪的原则是（）时的噪声。
A、优先降低大信号
B、不区分大小信号
C、不必降低小信号
D、优先降低小信号
参考答案：A
The two friends ______ everything, they had no secret. [ ]
A. had
B. shared
C. liked
D. enjoyed
托收的业务品种有哪几种？（）
A.收到委托收款
B.发出委托收款
C.发出托收结算
D.收到委托承付
E.发出委托承付
F.定期代收结算
