Britney Spears is definitely back! After announcing the launch of her lingerie line in July, the Work B**ch singer showed off her bangin' body by posting an Instagram pic on Aug. 6, 2014 of her only wearing a crop-top sweater and underwear. Britney wrote: "Amazing amazing shoot with @jefflipsky today! Been working hard this summer! So ready to bring it for the next round of #PieceOfMe shows next week."