function changePic(a,flag)
       {
           var title=document.getElementById("item"+a);
           var text=document.getElementById("about_text"+a);
           if(flag)
           {
              title.src="images/about_"+a+".gif";
              for(var i=1;i<=4;i++)
              {
                  document.getElementById("item"+i).src="images/about_"+i+".gif";
              }
           }
           else
           {
              title.src="images/about_"+a+"0.gif";
              text.style.display="block";
              for(var i=1;i<=4;i++)
              {;
                  if(i!=a)
                  {
                   document.getElementById("item"+i).src="images/about_"+i+".gif";
                   document.getElementById("about_text"+i).style.display="none";
                  }
              }
           }
       }