function show_tbl(pre,n,select_n,anchor_point){			
			if(pre=="tbl_video_")
			{
				if(select_n=="1")
				{
					if(document.getElementById("tb_video")!=null)
					{
					document.getElementById("tb_video_1").bgColor="#0099ff";
					document.getElementById("tb_video").bgColor="#ccebfd";
					}
				}
				else
				{
					document.getElementById("tb_video_1").bgColor="#ccebfd";
					document.getElementById("tb_video").bgColor="#0099ff";
				}
			}
				for(i=1;i<=n;i++){
					var tbl=document.getElementById(pre+i);
					tbl.style.display="none";
					if(i==select_n){
						tbl.style.display="block";
					}
				}
				if(anchor_point!=""){
					window.location.href(anchor_point)
				}
			}