function zeige1() {
var getsmal =  window.document.aa.src;
var getsmal = getsmal.substring(0,getsmal.length-6);

var getbig =  window.document.gr.src;
var getbig = getbig.substring(0,getbig.length-6);

window.document.gr.src=getsmal+"gr.jpg";
window.document.aa.src=getbig+"kl.jpg";

}

function zeige2() {
var getsmal =  window.document.bb.src;
var getsmal = getsmal.substring(0,getsmal.length-6);

var getbig =  window.document.gr.src;
var getbig = getbig.substring(0,getbig.length-6);

window.document.gr.src=getsmal+"gr.jpg";
window.document.bb.src=getbig+"kl.jpg";
}
function zeige3() {
var getsmal =  window.document.cc.src;
var getsmal = getsmal.substring(0,getsmal.length-6);

var getbig =  window.document.gr.src;
var getbig = getbig.substring(0,getbig.length-6);

window.document.gr.src=getsmal+"gr.jpg";
window.document.cc.src=getbig+"kl.jpg";
}