if (document.images) {
  img1on = new Image();
  img1on.src = "../images/bhome2.jpg";
  img2on = new Image();
  img2on.src = "../images/baboutus2.jpg";
  img3on = new Image();
  img3on.src = "../images/bproducts2.jpg";
  img4on = new Image();
  img4on.src = "../images/bcourses2.jpg";
  img5on = new Image();
  img5on.src = "../images/bcontact2.jpg";
  img6on = new Image();
  img6on.src = "../images/buttonbuy2.jpg";
  img8on = new Image();
  img8on.src = "../images/bcorporate2.jpg";
  

  img1off = new Image();
  img1off.src = "../images/bhome1.jpg";
  img2off = new Image();
  img2off.src = "../images/baboutus1.jpg";
  img3off = new Image();
  img3off.src = "../images/bproducts1.jpg";
  img4off = new Image();
  img4off.src = "../images/bcourses1.jpg";
  img5off = new Image();
  img5off.src = "../images/bcontact1.jpg";
  img6off = new Image();
  img6off.src = "../images/buttonbuy1.jpg";
  img8off = new Image();
  img8off.src = "../images/bcorporate1.jpg";
  
  
}

function turnOn(imageName) {
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  }
}

function turnOff(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "off.src");
  }
}