问题
选择题
圆面积扩大16倍，则周长随着扩大（ ）
A．32倍
B．16倍
C．8倍
D．4倍
答案
因为S=πr2，所以面积扩大16倍，半径扩大4倍，
又因为C=2πr，所以半径扩大4倍，周长就扩大4倍，
故选：D．
搜题请搜索小程序“爱下问搜题”
圆面积扩大16倍，则周长随着扩大（ ）
A．32倍
B．16倍
C．8倍
D．4倍
因为S=πr2，所以面积扩大16倍，半径扩大4倍，
又因为C=2πr，所以半径扩大4倍，周长就扩大4倍，
故选：D．
从方框中选择恰当的句子完成下面的对话，并将其字母标号填在答题纸的相应位置上 Dick: Hello . 1 What’s your name? Sally: Hello, Mr. Turner., I’m Sally Brown. I am from England. I’ve come to Japan to have a visit. Dick: I come from America. I’ve been here to study Japanese. 2 Sally: Oh, good. And could you tell me who this is , Mr. Turner? Dick: Oh, Ms Brown., 3 Sally: Nice to meet you, Mr. Wang. Wang Bing: 4 Sally: By the way, where are you from? Wang Bing: 5 Sally: Oh, great. China is a great beautiful country. Wang Bing: Thank you.
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