function changeForm(){
    var formName="itemForm";
    if(document.forms.formten.product[0].selected){
        document.forms.formten.price.value = 19;
    }else if(document.forms.formten.product[1].selected){
        document.forms.formten.price.value = 29;	
    }else if(document.forms.formten.product[2].selected){
        document.forms.formten.price.value = 39;	
    }
}

function changeFormS(s_price, s_change){
	var formName="itemForm";
	if(document.forms.formten.product[0].selected){
		document.forms.formten.price.value = s_price;
	}else if(document.forms.formten.product[1].selected){
		document.forms.formten.price.value = s_price+s_change;
	}else if(document.forms.formten.product[2].selected){
		document.forms.formten.price.value = s_price+s_change*2;
	}
}