DJBenz
Loving YTtalk
Yes you can and most probably you will get a copy right strike with Perry's song.
Nope, see the screenshot above. You'll get a Content ID match and the video it's in can't be monetized. While there's good advice in avoiding copyrighted material, many companies have caught on to the fact that they can earn money by taking the monetization from videos that use their material, so they choose to allow and take the money rather than block and strike.
Of course, it could all change at any time, but you also hear stories of copyright-free material changing status and people getting Content ID claims, so who knows?