在中国当代文坛上，有一位非常著名的女作家，她的早期作品有《哦，香雪》、《没有纽扣的红

Here is the bulletin board of Class 3. Some of the students put their notes on it. Please read them and answer the following questions.

小题1:The Chinese meaning of "bulletin board" is _______.

A．电影广告

B．寻人启事

C．公告栏

D．通缉令小题2:According to the notes on the bulletin board, what holiday might be coming?

A．Christmas

B．Halloween

C．Thanksgiving

D．New Year's Day小题3:When Julia is busy, what does Alex always help her do?

A．To do math homework.

B．To clean the windows.

C．To have P. E. class together.

D．To take books to school.小题4:From the bulletin board, we know that Mr Chen is a ___________.

A．repeater

B．P.E. teacher

C．doctor

D．pilot小题5:Why does Bill lend books to Mario?

A．They are classmates.

B．Miss Li wants him to do so.

C．Bill has too many books.

D．Mario forgot to bring his books to school.

有三瓶无色、无气味的气体A、B、C，它们分别是氢气、一氧化碳、甲烷中的一种。点燃气体，用干燥的冷烧杯罩在火焰上方，在B、C火焰上方的烧杯内壁上有水珠出现，而在A火焰上方的烧杯内壁上没有水珠。燃烧后，分别向烧杯中注入澄清石灰水，振荡，A、B杯内的石灰水变浑浊，C杯内没有变化。则 （1）A是             ，B是              ，C是              。

（2）试写出实验中所有反应的化学方程式：

                             ；                          ；

                             ；                           。

影响女子胞功能的生理因素有哪些？

货物流动的特定渠道称为（）

A.生产路径

B.市场渠道

C.产能路径

D.分销渠道

分析在四线制转辙机表示电路中，4μF电容断线会出现什么现象？表示外线的交直流电压大约是多少？为什么？