The traffic lights at three different crossings turn red after every 30 sec, 45 sec and 60 sec, respectively. If they all tum red simultaneously at 8:30 a.m., then at what time will they again turn red simultaneously?
1
8:33 a.m.
2
8:35 a.m.
3
8:38 a.m.
4
8:34 a.m.