Perform the following three XPath queries on the XML Document below:

 //item[1]: Retrieve the first "item" element 
 //price/text(): Perform an action on each "price" element (print it out)
 //name: Get an array of all the "name" elements
XML Document:

<inventory title="OmniCorp Store #45x10^3">
  <section name="health">
    <item upc="123456789" stock="12">
      <name>Invisibility Cream</name>
      <price>14.50</price>
      <description>Makes you invisible</description>
    </item>
    <item upc="445322344" stock="18">
      <name>Levitation Salve</name>
      <price>23.99</price>
      <description>Levitate yourself for up to 3 hours per application</description>
    </item>
  </section>
  <section name="food">
    <item upc="485672034" stock="653">
      <name>Blork and Freen Instameal</name>
      <price>4.95</price>
      <description>A tasty meal in a tablet; just add water</description>
    </item>
    <item upc="132957764" stock="44">
      <name>Grob winglets</name>
      <price>3.56</price>
      <description>Tender winglets of Grob. Just add water</description>
    </item>
  </section>
</inventory>

#Example taken from the REXML tutorial (http://www.germane-software.com/software/rexml/docs/tutorial.html)
require "rexml/document"
include REXML
#create the REXML Document from the string (%q is Ruby's multiline string, everything between the two @-characters is the string)
doc = Document.new(
        %q@<inventory title="OmniCorp Store #45x10^3">
             ...
           </inventory>
          @
                          )
# The invisibility cream is the first <item>
invisibility = XPath.first( doc, "//item" ) 
# Prints out all of the prices
XPath.each( doc, "//price") { |element| puts element.text }
# Gets an array of all of the "name" elements in the document.
names = XPath.match( doc, "//name" )