Hall of Famer Norm Duke slowed his pace to a 240 average, but retained the lead after Tuesday’s second round of the Florida Blue Medicare PBA50 National Championship, according to results posted here. Duke, who averaged 264 with 1,584 in Monday’s first round on the burn squad, added 1,300 on Tuesday on th fresh squad for a 2,884 12-game total (240.33 average) at Spanish Springs Lanes in The Villages, Florida. He bowls on the double burn squad on Wednesday. “Today was...