An engineer believes that W, the weight that a structure can support without structural damage, has a normal distribution with mean 300000 kg and standard deviation 10000 kg. has a normal distribution with mean 300000 kg and standard deviation 10000 kg. If cars pass by with a weight that has an expected value of 900 kg with standard deviation 200 kg, how many cars must be on the bridge for structural damage to occur? Calculate the number of cars for different probabilities of structural damage (0.1,0.25,0.5,0.75,0.99). If 25 cars pass, what is the weight distribution of these 25 cars?