Procter & Gamble and Facebook have nothing in common. One deals in razors and toothpaste, the other in likes, self-promotion and embarrassing family photos. But this week, they shared the same problem: the strong dollar has taken a cut of their quarterly sales. It has been a widespread complaint this first-quarter earnings season. Big companies of all stripes said their quarters would have been much better if it weren't for the rising dollar. Delta Air Lines said it hurt ticket sales. Johnson & Johnson blamed it for dragging earnings down. "Everybody is talking about the hit from the dollar, especially big ... (full story)