function showimg20(){
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}
function showimg21(){
     document.sea1.src = "http://akit.jp/index/wp-content/uploads/2011/02/sea0003.jpg";
}
function showimg22(){
     document.sea1.src = "http://akit.jp/index/wp-content/uploads/2011/02/sea0004.jpg";
}
function showimg23(){
     document.sea1.src = "http://akit.jp/index/wp-content/uploads/2011/02/sea0002.jpg";
}