Hixon, a silver medalist at the 2016 Rio Games, and recent NCAA champion Copobianco won handily with 1,289.27 points. Greg Duncan and Grayson Campbell took second at 1,168.80.
Hixon and Copobianco capped off their list with a forward 4 1/2 somersault tuck that earned 90.6 points for a dive with a 3.8 degree of difficulty.
Parratto, a 2016 Olympian, and Schnell were consistent throughout the final round, finishing with 930.00 points. Katrina Young, who made the Olympic team in 2016, and Murphy Bromberg finished second at 888.54.
Krysta Palmer and Alison Gibson made the U.S. team by winning the women's 3-meter synchro on Thursday.
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