开心消消乐855关攻略:math! math!!!
来源:百度文库 编辑:中科新闻网 时间:2024/05/07 10:54:19
a circilar pond 40 feet in diameter is surrounded by a patch of grass two feet wide. what is the area of the grass?
3.14*(22^2-20^2)约=264 feet^2 = 24.5 square meter
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来源:百度文库 编辑:中科新闻网 时间:2024/05/07 10:54:19
3.14*(22^2-20^2)约=264 feet^2 = 24.5 square meter