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4-82 The demand for water use in Phoenix in 2003 hit a high of about 442 milion gallons per day on June 27. Water use in the summer is normally distributed with a mean of 310 million gallons per day and a standard devation of 45 million gallons per day. City reservoirs have a combined storage capacity of nearly 350 million gallons. (a) What is the probability that a day requires less water than is stored in city reservoirs? (b) What reservoir capacity is needed so that the proability that it is exceeded is 5%. (c) What amount of water use is exceeded with 99% probability? (d) Water is provided to approximately 1.4 million people. What is the mean daily consumption per person at which the probability that the demand exceeds the curret reservoir capacity is 2%? Assume that the standard deviation remains the same.