when I click on the link for the posts http://www.telechargercours.com/post-sitemap.xml I receive an error

XML Parsing Error: not well-formed
Location: http://www.telechargercours.com/post-sitemap.xml
Line Number 14427, Column 34: L'Ordre SELECT √Čl√©mentaire</image:caption>

any idea about this error?

here is my code in the theme:

<div id="Ads1">Ads1</div>
<div id="Ads2">Ads2</div>

and the css is:

#Ads1 {
    float: left;
    width: 728px;
    height: 90px;
    margin-left: 152px;
    padding-bottom: 5px;
    padding-top: 5px;
}

#Ads2 {
    float: left;
    width: 200px;
    height: 90px;
    margin-left: 32px;
    padding-bottom: 5px;
    padding-top: 5px;
}

please I'm not familiar with css, can you give me the correct code to do the same thing

I created a div zone for advertising on top of my site, but when I reduce or increase the size of the pages [Ctrl +] or [Ctrl -].advertising is not reduced.