function changeEdit() {

	if (document.calculator.video_edit.selectedIndex==0)
	{
		document.calculator.more_dvd_copies.disabled = true
		document.calculator.more_vhs_copies.disabled = true
	}
	else {
	document.calculator.more_dvd_copies.disabled = false
	document.calculator.more_vhs_copies.disabled = false
	}
}

function changeOper() {

	if (document.calculator.oper_work.selectedIndex==0)
	{
		document.calculator.nemont_dvd.disabled = true
	}
	else {
	document.calculator.nemont_dvd.disabled = false
	}
}