If you want place the ads in RSS feed that is very easy with wordpress websites.
You can use following code for showing the ads in rss feeds.
Open your functions.php file from wordpress theme folder and use following code:

function insertAds_in_rss($content) {

$content = $content.' Your ads code goes will here';

return $content;}

add_filter('the_content_feed', 'insertAds_in_rss');

add_filter('the_excerpt_rss', 'insertAds_in_rss');

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