function js_challenge1()
{
//	alert("Removing the top ruler.");
	sajax_target_id = 'ruler'; 
	x_p_clear(); 
	sajax_target_id = '';
//	alert("Filling the left column");
	sajax_target_id = 'leftcol'; 
	x_p_challenge1a(); 
	sajax_target_id = '';
//	alert("Showing the next challenge");
	sajax_target_id = 'centercol'; 
	x_p_challenge1b(); 
	sajax_target_id = '';
}
function js_challenge2()
{
//	alert("js_challenge2");
	sajax_target_id = 'centercol'; 
	x_p_book(); 
	sajax_target_id = '';
}
function js_write_right()
{
	sajax_target_id = 'contents'; 
	x_p_contents(); 
	sajax_target_id = '';
	sajax_target_id = 'belowbook'; 
	x_p_belowbook(); 
	sajax_target_id = '';
}
function js_overflow()
{
	sajax_target_id = 'rightpage'; 
	x_p_overflow(); 
	sajax_target_id = '';
	sajax_target_id = 'belowbook'; 
	x_p_belowbook2(); 
	sajax_target_id = '';
}
function js_challenge3()
{
	sajax_target_id = 'rightcol'; 
	x_p_challenge3(); 
	sajax_target_id = '';
	window.scrollTo(0,0);
}
function js_mobile()
{
	sajax_target_id = 'rightcol'; 
	x_p_mobile(); 
	sajax_target_id = '';
}
function js_download(product)
{
	sajax_target_id = 'hide'; 
	x_p_download(product); 
	sajax_target_id = '';
}