Viski Vemmelsri specializes in triple jumping. In this sport, the overall performance is divided into three parts, a leap, a step and a jump. In the measurements carried out during the season, it was found that the parts of V emmelsri's performances follow a normal distribution approximately as follows: ~ (5.6, 0.42), ~ (5.0, 0.72) and ~ (6.1, 0.82).

We also assume that successive jumps are independent of each other. If Vemmelsri does six jumps during the triple jump competition, what is the probability that at least two of them are over 18 meters long?