function showTab(iActive, iTabs) {
  var sHead  = "";
  var sBody  = "";
  var sClass = "";
  for (i = 0; i < iTabs; i++) {
    sHead = "head" + i;
    sBody = "body" + i;
    if (i == iActive) {
      sClass = "active";
    } else {
      sClass = "normal";
    }
    document.getElementById(sHead).className = sClass;
    document.getElementById(sBody).className = sClass;
  }
}