Describir: The effect of handle height and cart load on the initial hand forces in cart pushing and pulling /

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