I think your blog is externally hosted.. If it is.. then, you can add Adsense on your site. Try to google for the related wordpress adsense plugins.. good luck.
If possible, get your own domain. I personally would not get a blog at blogger or wordpress.com because it doesn't allow the freedom that I have with my own self-hosted one.
I use whydowork adsense - http://www.whydowork.com/blog/whydowork-adsense-plugin/ - set it up and set it up correctly. Then leave it. Works great for me
If its ona subdomain like: site.wordpress.org then NO if its your own TLD or something and hosted somewhere else then YES
If you own a TLD and hosting.. Then yes of course if you got a blog on wordpress.com then no You may put on blogspot.com
If you are doubtful whether your website is in accordance with Google Adsense TOS, simply send them the URL of your website for them to review your website. They shall review it and follow up with you eventually.
Yes, you can if your website do not commit in accordance with Google Adsense TOS. Fill form and send it to Google Ads Team for them to review your website. Visit my site http://games.diendan.vn