function selectTab(id)
{
	switch(id)
	{
		case 1:
			document.getElementById('cover1').style.display = 'block';
			document.getElementById('cover2').style.display = 'none';
		break;
		case 2: 
			document.getElementById('cover1').style.display = 'none';
			document.getElementById('cover2').style.display = 'block';
		break;
		default: 
			document.getElementById('cover1').style.display = 'block';
			document.getElementById('cover2').style.display = 'none';
		break;
	}
}