Reading data from xml file

I have a currency converter开发者_StackOverflow中文版 application for iphone which uses web service. The web service is returning result in the following format:-

            <Date>4/5/2010</Date>
            <Time>7:18:09 AM</Time>
            <Amount>20</Amount>
            <ExchangeRate>44.7336419443466</ExchangeRate>
            <Result>894.672839</Result>

I'm storing the whole xml file in an NSString variable called theXML. I want to show the value inside the result tag.How can i read the data from the xml file or from the string..

Thanks in advance..

Use XPath.