function submenu_hyouzi(w_id,w_this,w_img_src)
{
  chng_image(w_this,w_img_src);
  hyouzi(w_id)
}

function submenu_hihyouzi(w_id,w_this,w_img_src)
{
  chng_image(w_this,w_img_src);
  hihyouzi(w_id)
}

function hyouzi(w_id)
{
  document.getElementById(w_id).style.visibility="visible"
}

function hihyouzi(w_id)
{
  document.getElementById(w_id).style.visibility="hidden"
}

function chng_background(w_this,w_img_src)
{
  w_this.background=w_img_src
}

function chng_image(w_this,w_img_src)
{
  w_this.background=w_img_src
}