發送短信

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   _____    ______               ___      ______  
  / ___//  /_   _//     ___     / _ \\   /_   _// 
  \___ \\   -| ||-     /   ||  / //\ \\    | ||   
  /    //   _| ||_    | [] || |  ___  ||  _| ||   
 /____//   /_____//    \__ || |_||  |_|| /__//    
`-----`    `-----`      -|_|| `-`   `-`  `--`     
                         `-`

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發送短信 : A Mathematical App for the Conceptual Understanding of Area and Perimeter