Please help!!!
<a>
<b>bar</b>
<b>bar</b>
<b>foo</b>
<b>bar</b>
</a>
With reference to the above XML. Taking a/b[4] as the context node,
desbribe an XPath that returns a node-set containing the first b
element
in reverse document order that contains the same text node as the
current
context.