“冷链”保存生物制品低温冷库所要求的温度是（） A.-70℃ B.0℃以下 C.4～

阅读理解。

     I have twin brothers, Tim arid Tom.  They look the same and a lot of people don't know which twin

is which.  They both have brown hair and blue eyes, and always wear jeans and T-shirts.

    They like wearing the same things, and they like doing the same things,too,For example, they both like

pop music, football and computers. They go to a football match every Saturday.  They'd like to play

computer games every night,,but  our mother says they can't because they have a lot of homework.

    They are twins, but they aren't the same in every way.  For example,Tim works hard at school, but

Tom doesn't.

    Our mother is often away from home because she travels a lot in her job,so we all help in the house.

    I think it's fun to have twin brothers.

1. My lwin brothers both have______hair and______eyes and always wear jeans and T-shirts.

A．red, black    

B.  white, grey

C. brown, blue    

D.  yellow, purple

2.  Tim and Tom both like______.

A.  pop music, model robots    

B.  computers, pop music

C. football, homework    

D.  housework, computers

3.  They go to a football match every______.

A. Friday    

B.  Saturday    

C.  Sunday    

D.  holiday

4. Tim______,but Tom doesn't.

A. sings well    

B.  can send e-mails at home

C. works hard at school    

D.  plays football very well

5.______often travels and doesn't often stay at home.

A.  The writer  

B.Tim    

C.Tom    

D.Their mother

下列关于重大错报风险的说法中，正确的有（）。

A.重大错报风险包括固有风险和检查风险

B.注册会计师应当将重大错报风险与特定的交易、账户余额和披露的认定相联系

C.在评估一项重大错报风险是否为特别风险时，注册会计师不应考虑控制对风险的抵消作用

D.注册会计师对重大错报风险的评估，可能随着审计过程中不断获取审计证据而做出相应的变化

下列各项中，可以作为作业成本计算理论依据的是（）。

A、作业消耗资源

B、产品消耗作业

C、直接人工成本的增加

D、间接费用的降低

E、成本性态分析

Si加热到2000K温度蒸发，然后Si原子在300K的基片上凝聚。试问：
①Si蒸发和凝聚时的蒸汽压分别为多少Pa
②欲实现Si在上述条件下蒸发和凝聚，真空罩中的真空应在什么范围内，并说明其原因。(已知Si的蒸汽压(p)和温度(t)关系中的系数：
A=13，B=2×10⁴，
式中，P的单位为μmHg，1μmHg=0.133Pa，T的单位为K

下列有关横道图的叙述，不正确的是( )。

A．横道图是一种最简单并运用最广的传统的计划方法

B．横道图用于小型项目或大型项目上，或用于计算资源需要量

C．横道图的另一种可能的形式是将工作简要说明直接放在横道上

D．因为有许多新的计划技术，所以横道图在建设领域中的应用不是很普遍