题干
根据对话内容，从方框中选择最佳选项，使对话意思完整、通顺，并将其字母序号写在对话后面的空格内。（其中有两个为多余选项）
A. Which bus can I take? B. Sorry, I don't know. I am new here. C. How far is it? D. How long is it from here? E. It's over there, across from the bank. F. Is there a post office near here? G. How often do you go there? |
A: Excuse me. Could you tell me the way to the nearest post office?
B: ____You can ask the policeman over there. He may help you.
A: Thank you all the same.
(One minute later)
A: Excuse me. ____
C: Sorry, there isn't a post office near here, but there is one near the bus station.
A: ____
C: It's about a quarter by bus.
A: ____
C: The No. 102 bus can take you there.
A: By the way, where's the bus stop?
C: ____
A: Thank you very much.
C: You're welcome.
答案(点此获取答案解析）
B,F,C,A,E
是等差数列
的前
项和，且
，
，则
等于（ ）