The waiting time of red stoplights at a random city is normally distributed with a population mean of 57 seconds and an unknown standard deviation.  (a) Find the standard deviation if the highest 14% of red stop lights is 64 seconds. Round to 2 decimal places. (b) Find the probability that the waiting time of a randomly selected red stop light is less than 49 seconds. Round to 4 decimal places. (c) Find the probability that the waiting time of a randomly selected red stop light is between 50 and 55 seconds. Round to 4 decimal places.

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