發送短信

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   _____     ___     ______      ___     _    _   
  / ___//   / _ \\  |      \\   / _ \\  | || | || 
  \___ \\  / //\ \\ |  --  //  | / \ || | || | || 
  /    // |  ___  |||  --  \\  | \_/ || | \\_/ || 
 /____//  |_||  |_|||______//   \___//   \____//  
`-----`   `-`   `-` `------`    `---`     `---`

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發送短信 : Developing a Game-Based Instructional Manipulative for Permutation and Combination