function boxChecked(box) {
      if (box.length) {
          for (i=0; i<box.length; i++) { 
               if (box[i].checked){
                   return true;
               } 
          }
      } else {
          if (box.checked) {
              return true;
          }
      }
      return false;
}
function setDisplay(objectID,state) {
	var object = document.getElementById(objectID);
	object.style.display = state;
}

var da = (document.all) ? 1 : 0;
var pr = (window.print) ? 1 : 0;
var mac = (navigator.userAgent.indexOf("Mac") != -1);
 
function printPage() {
  if (pr) // NS4, IE5
    window.print()
  else if (da && !mac) // IE4 (Windows)
    vbPrintPage()
  else // other browsers
    alert("Sorry, your browser doesn't support this feature.\nTo print, from the File Menu or Tool Bar, select Print.");
  //return false;
}

function policyWindow() {
   var url = 'http://maththinking.com/MathThinkingLicenseHandlingPolicy.html';
   historywin=dhtmlwindow.open('policyWindow', 'iframe', url, 'MathThinking License Policy', 'width=750px,height=480px,resize=1,scrolling=1,center=0', 'blue');
}