I saw your advert in the paper ethinyl estradiol and estradiol valerate differences * Facebook Inc, which has repeatedly tripped over itsown feet when changing its privacy practices, has stumbled yetagain. The Federal Trade Commission said on Wednesday that ithad begun an inquiry into whether the social network’s proposednew privacy policies, unveiled two weeks ago, violated a 2011agreement with regulators. Under that agreement, the socialnetwork is required to get the explicit consent of its usersbefore exposing their private information to new audiences. ()