Clyde cement wants to analyze a shipment of bags of cement. he knows the weight of the bags is normally distributed so he can use the standard normal distribution. he measures the weight of 600 randomly selected bags in the shipment. next, he calculates the mean and standard deviation of their weights. the mean is 50 lbs and the standard deviation is 1.5 lbs. what percentage of the bags of cement will weigh less than 50 lbs.?