Along with her song "Will You Still Love Me tomorrow" which made 76 on the Hot 100, Roberta Flack has also performed many duets, including "Where Is The Love" with which singer?
Quiet Fire:  The album peaked at number 18 on the "Billboard" Top LPs & Tape, and its single "Will You Still Love Me Tomorrow" charted at number 76 on the Hot 100. Roberta Flack:  She is best known for her classic #1 singles "The First Time Ever I Saw Your Face", "Killing Me Softly with His Song" and "Feel Like Makin' Love", and for "Where Is the Love" and "The Closer I Get to You", two of her many duets with Donny Hathaway.
Donny Hathaway