function toggleAbout() {
        document.getElementById('About').style.display = 'block'
        document.getElementById('Sample').style.display = 'none'		
        document.getElementById('About4FT').style.display = 'none'
        document.getElementById('Why').style.display = 'none'
        document.getElementById('What').style.display = 'none'
		document.about.src='img/nav_about_ft_o.gif'
		document.about4ft.src='img/nav_about_4ft.gif'
		document.sample.src='img/nav_about_sample.gif'		
		document.why.src='img/nav_why_ft.gif'
		document.what.src='img/nav_what_ft.gif'		
    }

function toggleSample() {
        document.getElementById('About').style.display = 'none'
        document.getElementById('Sample').style.display = 'block'		
        document.getElementById('About4FT').style.display = 'none'
        document.getElementById('Why').style.display = 'none'
        document.getElementById('What').style.display = 'none'
		document.about.src='img/nav_about_ft_o.gif'
		document.about4ft.src='img/nav_about_4ft.gif'
		document.sample.src='img/nav_about_sample.gif'		
		document.why.src='img/nav_why_ft.gif'
		document.what.src='img/nav_what_ft.gif'		
    }

function toggleAbout4FT() {
        document.getElementById('About').style.display = 'none'
        document.getElementById('Sample').style.display = 'none'		
        document.getElementById('About4FT').style.display = 'block'
        document.getElementById('Why').style.display = 'none'
        document.getElementById('What').style.display = 'none'
		document.about.src='img/nav_about_ft.gif'
		document.sample.src='img/nav_about_sample.gif'		
		document.about4ft.src='img/nav_about_4ft_o.gif'
		document.why.src='img/nav_why_ft.gif'
		document.what.src='img/nav_what_ft.gif'	
}

function toggleWhy() {
        document.getElementById('About').style.display = 'none'
        document.getElementById('Sample').style.display = 'none'		
        document.getElementById('About4FT').style.display = 'none'
        document.getElementById('Why').style.display = 'block'
        document.getElementById('What').style.display = 'none'
		document.about.src='img/nav_about_ft.gif'
		document.sample.src='img/nav_about_sample.gif'		
		document.about4ft.src='img/nav_about_4ft.gif'
		document.why.src='img/nav_why_ft_o.gif'
		document.what.src='img/nav_what_ft.gif'			
    }

function toggleWhat() {
        document.getElementById('About').style.display = 'none'
        document.getElementById('Sample').style.display = 'none'		
        document.getElementById('About4FT').style.display = 'none'
        document.getElementById('Why').style.display = 'none'
        document.getElementById('What').style.display = 'block'
		document.about.src='img/nav_about_ft.gif'
		document.sample.src='img/nav_about_sample.gif'		
		document.about4ft.src='img/nav_about_4ft.gif'
		document.why.src='img/nav_why_ft.gif'
		document.what.src='img/nav_what_ft_o.gif'			
    }