完形填空。Last autumn I spent a week at a big
题型：完形填空
问题：
| 完形填空。 | ||||
| Last autumn I spent a week at a big hotel in London. It was one of those modern hotels 1 every room is the same size 2 has the same furniture looking just like 3 other room. My room was 311. One 4 , I got back to the 5 after a dinner with some friends. When I opened the door to my room I saw a(n) 6 scene. A man was pointing a handgun 7 a woman sitting in a chair, and the woman was saying in a terrible voice: "Please don't shoot me!" I turned round, ran down the stairs-I daren't wait for the 8 -and found a waiter in the hall. "Quick," I cried, "someone is being 9 in my room." Controlling his surprise he came back with me, 10 when we opened the door of 311, the room was 11 . The waiter looked at me 12 and said: "I think, sir, you 13 go to bed," and left. I was 14 puzzled to say anything, and thinking that I must have had too much to 15 , I followed his 16 . The next morning, I asked about the matter, and the 17 was simple, I had gone to Room 411, where a famous 18 and his wife had been practising a scene from their new 19 . When I told them that it was I who had rushed into their room, they laughed and gave me a 20 to see the play for the opening night. | ||||
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of the circumference of a circle with radius 2 feet on top of an isosceles triangle with height 5 feet, as shown above. What is the perimeter, in feet, of the sign ？（）