临床常用的印模材料是A．印模石膏 B．藻酸盐类印模材料 C．琼脂胶体 D．硅橡胶印模

设f（x）在（-∞，+∞）上是减函数，且a+b≤0，则下列各式成立的是（　　）

A．f（a）+f（b）≤0

B．f（a）+f（b）≥0

C．f（a）+f（b）≤f（-a）+f（-b）

D．f（a）+f（b）≥f（-a）+f（-b）

单句改错

小题1:He is as clever boy as his brother

小题2:I consider this impossible to finish this task on time.

小题3:He like swimming in particularly in summer.

小题4:I could hardly find suitable words express myself.

小题5:You should suit yourself to the new environment.

小题6:We were out of breathe when we reached the top of hill.

小题7:you should keep your words after you promise to help.

小题8:I’d like to have gone to the party last night but I had to finished a report.

小题9:I hate being made fun.

小题10:John would rather stay at home than going out.

下列表面活性剂有起昙现象的主要是哪一类

A．肥皂

B．硫酸化物

C．磺酸化物

D．季铵化物

E．吐温

“应收票据”科目应按( )作为入账金额。

A．票据面值

B．票据的到期价值

C．票据面值加应计利息

D．票据贴现额