It's a gray area, if you rewrite it totally and you can even claim it's your own work own idea. If you just rewrite a little, for SEO, should be ok. Also you can spin it, make it more more unique http://seo.x-y.in/Tools/Article-Spin-Format-Spinner/ As long as it unique, nobody will find out it's a rewrite anyway
probably correct, although how many times have you started to read something, and gone... hang on.. *I* wrote that! (or something like it, anyway!)