Describir: Building Unit construction, prep. especially for home study

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  / ___//   / _ \\  | || | || | || | ||  | |/ //   / _ \\      ___     / _ \\  
  \___ \\  / //\ \\ | '--' || | || | ||  | ' //   | / \ ||    /   ||  | / \ || 
  /    // |  ___  ||| .--. || | \\_/ ||  | . \\   | \_/ ||   | [] ||  | \_/ || 
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`-----`   `-`   `-` `-`  `-`    `---`    `-` --`   `---`       -|_||   `---`   
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