[Plugin: AdSense Manager] How to delete an ad once created in WordPress and how to position

Once I’ve added an ad in WordPress, how can I delete it? I can’t find any option for deleting the ad under Manage> Ad Units or anywhere else.

Also, how do you set up where the ad will appear on the page or post?

And, let me add my interest in having more detail on where to insert the ad#name code and exactly how it should look. Thanks!