function caracteres(){
document.form.qtc.value = 72-document.form.descricao.value.length;
if(document.form.descricao.value.length >71){
document.form.descricao.value = document.form.descricao.value.substring(0,75);
}
}
function escreve() {
document.getElementById("spandesc").innerHTML=document.form.descricao.value;
}