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  image2on = new Image();
  image2on.src = "../images/buttons/senior_out-butb.jpg";

  image3on = new Image();
  image3on.src = "../images/buttons/suicide-butb.jpg";
  
  image4on = new Image();
  image4on.src = "../images/buttons/volunteering-butb.jpg";

  image1off = new Image();
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  image2off.src = "../images/buttons/senior_out-buta.jpg";

  image3off = new Image();
  image3off.src = "../images/buttons/suicide-buta.jpg";

  image4off = new Image();
  image4off.src = "../images/buttons/volunteering-buta.jpg";
}