Do you know when to tip and when to pass?

The clerk at your favorite bakery or local clothing boutique swipes your credit card and spins an electronic screen around that asks whether you want to tip. Do you select 15%, 20%, or 25% for being handed a croissant or for being shown to the dressing room? Or do you select “no tip” under the awkward gaze of the clerk? Learn how to handle awkward electronic tipping scenarios in this month’s “Do You Know?”