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	setTabClick('nav_osa','choice_osa');
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	setTabClick('nav_oka','choice_oka');
};

function hideHeading() {
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	hide('choice_osaHeading');
	hide('choice_ngoHeading');
	hide('choice_spkHeading');
	hide('choice_okaHeading');
}

function showContents(contentName){
	hide('choice_tyo'); 
	hide('choice_osa'); 
	hide('choice_ngo'); 
	hide('choice_spk'); 
	hide('choice_oka'); 
	show(contentName);
	chengeTabs(contentName);
}
function chengeTabs(contentName){
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}

function setTabClick(li,div) {
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	e.contents = div;
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}

function hide(elementId) {
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}
function show(elementId) {
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}