In the form below, add an input field with the type "button" and the value "OK".
<form>
<@(30)>
</form>
<form>
<input type="button" value="OK">
</form>
<form>
<input type='button' value='OK'>
</form>
<form>
<input value="OK" type="button">
</form>
<form>
<input value='OK' type='button'>
</form>