if (document.images) {
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    graphic1.src = "images/r_1";
  
    var graphic2 = new Image(); 
    graphic2.src = "images/r_2";

    var graphic3 = new Image(); 
    graphic3.src = "images/r_3";

    var graphic4 = new Image(); 
    graphic4.src = "images/r_4";

    var graphic5 = new Image(); 
    graphic5.src = "images/r_5";
}