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  introOn.src = "kc_title_on.gif";
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  basicOn = new Image();
  basicOn.src = "button_tutorial_on.gif";
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  basicOff.src = "button_tutorial_off.gif";

  advOn = new Image();
  advOn.src = "button_class_adv_on.gif";
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  treatOn = new Image();
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  analOn = new Image();
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  gridsOn = new Image();
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}
function turnOn(imageName) {
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}
function turnOff(imageName) {
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// -->