<?xml version = "1.0” encoding = "UTF-8"? > <doc> <a> <b> <a/> <a/> </b> <b> <a/> </b> <b> <a/> <a> <b/> <b/> </a > <a/> </b> </a> </doc> Convert each of the following queries into the corresponding XPath expression, and evaluate it on the tree by listing the pre-identifier of the nodes returned. i. For every element child m of some element node, and for every node n that is the third among all b-labelled element children of m, return the node that is the second among all element children for some descendant-or-self node of n.

<?xml version = "1.0” encoding = "UTF-8"?> <root> <a> <b> <a/> <a/> </b> <b> <a/> </b> <b> <a/> <a> <b/> <b/> </a > <a/> </b> </a> </root>Write down the XML document that corresponds to this tree.

Write down the following English language queries in XQuery, and show the result of evaluating the XQuery query on the given XML document. (a) For every distinct location l for which no trek with rating less than 85 exists, return an element node with label location that has the following content: i) a child element labelled location name with the name of the location as text content, and ii) for each trek in that location, an element child labelled trek with the name of the trek as text content.

Consider the following XML document. <?xml v e r si o n = ‘ ‘1.0”? > <walks> <t r e k name= ‘ ‘ Keple r”> <l o c a ti o n >Fi o rdl and </l o c a ti o n > <d i f f i c u l t y >moderate</ d i f f i c u l t y > <len g th >60km</len g th> <r a ti n g >88</ r a ti n g > </t re k> <t r e k name= ‘ ‘ Routeburn”> <l o c a ti o n >Fi o rdl and </l o c a ti o n > <d i f f i c u l t y >moderate</ d i f f i c u l t y > <len g th >32km</len g th> <r a ti n g >98</ r a ti n g > </t re k> <t r e k name= ‘ ‘ T on g a ri r o C r o s si n g”> <l o c a ti o n >Tongariro </l o c a ti o n > <d i f f i c u l t y >hard</ d i f f i c u l t y > <len g th >19.4km</len g th> <r a ti n g >96</ r a ti n g > </t re k> <walks>For every distinct location l for which no trek with rating less than 85 exists, return an element node with label location that has the following content: i) a child element labelled location name with the name of the location as text content, and ii) for each trek in that location, an element child labelled trek with the name of the trek as text content.

What is the basic syntax of XPath?

<?xml version = "1.0” encoding = "UTF-8"?> <root> <a> <b> <a/> <a/> </b> <b> <a/> </b> <b> <a/> <a> <b/> <b/> </a > <a/> </b> </a> </root>With respect to the given context node, marked in pink, evaluate the following axes on the tree. List the pre-identifier of each node that each axis returns. i. following::a ii. ancestor-or-self::node() iii. preceding-sibling::b