1. The demand for high-grade gasoline at a service station is normally distrib- uted with mean 27,009 gallons per day and standard deviation 4,530. Find two values that will give a symmetric 0.95 probability interval for the amount of high-grade gasoline demanded daily.

2. The percentage of protein in a certain brand of dog food is a normally distributed random variable with mean 11.2% and standard deviation 0.6%. The manufacturer would like to state on the package that the product has a protein content of at least x1% and no more than x 2%. It wants the statement to be true for 99% of the packages sold. Determine the values x1 and x 2.