<html><head></head><body>
<form name="f">
<p>商品代金</p>
1<input type="text" name="i0"><br>
2<input type="text" name="i1"><br>
3<input type="text" name="i2"><br>
4<input type="text" name="i3"><br>
<p>送料</p>
<input type="text" name="i4">
<p>代引き</p>
<select name="i5">
<option value="315">A(315円)</option>
<option value="420">B(420円)</option>
</select>
<p>
<input type="button" value="計算" onClick="func();">
<input type="text" name="i6" value="結果">
</p>
</form>
<script type="text/javascript">
var doc=document.f;
function func(){
doc.i6.value=(eval(doc.i0.value)+eval(doc.i1.value)+eval(doc.i2.value)+eval(doc.i3.value)+eval(doc.i4.value)+eval(doc.i5.value))*1.05;
}
</script>
</body></html>