公共汽车上的一些设施和做法与物理原理相对应，其中正确的是（　　）

某通讯公司需要在三角形地带OAC区域内建造甲、乙两种通信信号加强中转站，甲中转站建在区域BOC内，乙中转站建在区域AOB内．分界线OB固定，且OB=（1+ $\sqrt{3}$ ）百米，边界线AC始终过点B，边界线OA、OC满足∠AOC=75°，∠AOB=30°，∠BOC=45°．设OA=x（3≤x≤6）百米，OC=y百米．

肺泡数量很多，外面包绕着____；肺泡壁和毛细血管壁都很薄，都是由____层上皮细胞构成的，这些特点有利于____和____之间进行气体交换．

问答句配对,在右栏中找出与左栏相对应的答句。

①Hello, my name is Daming. ____      A. My telephone number is 56778843.

② How old are you? ____               B. P-E-N-C-I-L.

③What's your telephone number? ____      C. Thank you!

④Can you help me? ____          D. It's fifteen

⑤Sit down, please. ____           E. It's black and white

⑥How do you spell "pencil"? ____     F. Hi, Tony. Nice to meet you.

⑦This is my friend, Tony. ____        G. Football.

⑧What's eleven and four? ____     H. I'm twelve 

⑨What color is it? ____            I. Hello, I am Tom!

⑩What's your favourite sport? ____     J. Yes, of course.