function page1(){
	document.getElementById('page1').style.display='block'
	document.getElementById('page2').style.display='none'
	document.getElementById('page3').style.display='none'
	document.getElementById('page4').style.display='none'
	}
function page2(){
	document.getElementById('page1').style.display='none'
	document.getElementById('page2').style.display='block'
	document.getElementById('page3').style.display='none'
	document.getElementById('page4').style.display='none'
	}
function page3(){
	document.getElementById('page1').style.display='none'
	document.getElementById('page2').style.display='none'
	document.getElementById('page3').style.display='block'
	document.getElementById('page4').style.display='none'
	}
function page4(){
	document.getElementById('page1').style.display='none'
	document.getElementById('page2').style.display='none'
	document.getElementById('page3').style.display='none'
	document.getElementById('page4').style.display='block'
	}