according to a government study among adults in the 25- to 34-year age group, the mean amount spent per year on reading and entertainment is $1,875. assume that the distribution of the amounts spent follows the normal distribution with a standard deviation of $640. (round your z-score computation to 2 decimal places and final answers to 2 decimal places.) a. what percent of the adults spend more than $2,775 per year on reading and entertainment?