img_M0 = new Image ();
img_M0.src = "Half-L-1.gif";
img_M1 = new Image ();
img_M1.src = "Half-L-2.gif";
img_M2 = new Image ();
img_M2.src = "Half-R-1.gif";
img_M3 = new Image ();
img_M3.src = "Half-R-2.gif";
img_M4 = new Image ();
img_M4.src = "Half-L-3.gif";
img_M5 = new Image ();
img_M5.src = "Half-L-4.gif";
img_M6 = new Image ();
img_M6.src = "Half-R-3.gif";
img_M7 = new Image ();
img_M7.src = "Half-R-4.gif";
img_M8 = new Image ();
img_M8.src = "Brief-1.gif";
img_M9 = new Image ();
img_M9.src = "Brief-2.gif";
img_Ma = new Image ();
img_Ma.src = "Arrow-1a.gif";
img_Mb = new Image ();
img_Mb.src = "Arrow-1b.gif";

function switch_image (img_id, img_obj)
 {var img = get_element (img_id);
  img.src = img_obj.src;}

function change_color (id, color)
 {document.getElementById(id).bgColor = color;}