function   showdiv1()   {   
          Div1   =   document.getElementById("div1");   
		  Div2   =   document.getElementById("div2"); 
          Div1.style.display   =   "block";   
          Div2.style.display   =   "none"; 
}   
    
function   showdiv2()   {   
			  Div1   =   document.getElementById("div1");   
			  Div2   =   document.getElementById("div2");
			  Div1.style.display   =   "none";   
              Div2.style.display   =   "block"; 
}