权利质押的权利凭证包括（）。
A.汇票
B.债券
C.存款单
D.股票
E.商标专用权
参考答案：A, B, C, D, E
单项式﹣2πab2的系数是（ ），次数是（ ）．
-It is what parents say and do that really matters in children’s character training.
-________.[ ]
A．Properly
B．Doubtfully
C．Simply
D．Absolutely
