窗口期

在Excel中可选取（）单元格。

A.单个

B.多个

C.连续

D.不连续

减数分裂过程中同源染色体间开始DNA交换发生在

A．细线期

B．偶线期

C．粗线期

D．双线期

阅读理解。

     Welcome to Franklin Hotel. To make you stay as enjoyable as possible, we hope you will use our facilities (设施) to the full.

     Dining Room: Breakfast is served in the dining room from 8:00 to 9:30 a. m. Also the room staff (服务员 ) may bring breakfast to your room at any time after 7:00 a. m. If this happens, please fill out a card and hang it

outside your door when you go to bed. Lunch is from 12:00 to 2:30 p. m. Dinner is from 7:30 to 9:00 p. m.

     Room Service: This operates 24 hours a day; phone the Reception desk, and your message will be passed

on to the room staff.

      Telephones: To make a phone call, dial (拨) 0 for Reception and ask to be connected. We apologize for

delays if the lines are very busy. There are also public telephones near the Reception desk. Tell Reception if

early calls are needed.

     Shop: The hotel shop is open for presents, gifts and goods from 9:00 a. m. to 5:30 p. m.

     Laundry: We have a laundry in the building, and we will wash, iron and return your clothes within 24 hours. Ask the room staff to collect them.

     Bar (酒吧):The hotel bar is open from 12:00 to 2:00 p. m. and 7:00 p. m. to 1:00 a. m.

     Banking: The Reception staff will cash cheques (兑现支票) and exchange any foreign money for you.

     You have come back to the hotel just to make an urgent (紧急) phone call. But you notice a lot of people

around the Reception desk. 

Judging from the notice, it would be quickest to ______ .

A. go to your room and phone from there

B. ask at the Reception desk

C. use one of the public telephones near the telephone desk

D. go out again and look for a public phone box

轴向直廓蜗杆的齿形在蜗杆的轴平面内为（）。

A.直线

B.渐开线

C.曲线

D.螺旋线

设栈S和队列Q的初始状态均为空，元素a1、a2、a3、a4、a5、a6依次通过栈S，一个元素出栈后即进入队列Q，若6个元素出队的顺序是a2、a4、a3、a6、a5、a1，则栈S的容量至少应是( )。

A．2

B．3

C．4

D．6