function fechacombustivel()
{
    document.getElementById('divcombustivel').innerHTML = "<img src='img/progress.gif'>";
    document.getElementById('divcombustivel').style.visibility='hidden';
}

function fechaplantio()
{
    document.getElementById('divplantio').innerHTML = "<img src='img/progress.gif'>";
    document.getElementById('divplantio').style.visibility='hidden';
}

function mostracombustivel()
{
    document.getElementById('divcombustivel').style.visibility='hidden';
    document.getElementById('divcombustivel').innerHTML = "<img src='img/progress.gif'>";
    document.getElementById('divcombustivel').style.visibility='visible';
}

function mostraplantio()
{
    document.getElementById('divplantio').style.visibility='hidden';
    document.getElementById('divplantio').innerHTML = "<img src='img/progress.gif'>";
    document.getElementById('divplantio').style.visibility='visible';
}

function mostramenu(id){
    document.getElementById(id).style.visibility = 'visible';
}

function escondemenu(id){
    document.getElementById(id).style.visibility = 'hidden';
}