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An employee wouldn't tell the customer who it was, but said the anonymous person paid off $20,000 worth of purchases.

"As my eyes filled with tears I vowed to pay it forward as often as I could," the customer said.

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Waymo autonomous vehicles operate across 65 square miles inside I-285 and have been involved in six incidents with Atlanta Public School buses since May. Waymo issued a recall because of their cars briefly stopping or slowing down before continuing forward while a bus was stopped and flashing its lights. (Courtesy of Atlanta Public Schools)

Credit: Courtesy of Atlanta Public Schools