A recent survey by the American Automobile Association showed that a family of two adults and two children on vacation in the United States will pay an average of $247 per day for food and lodging with a standard deviation of $60 per day. Assuming the data are normally distributed, find, to the nearest hundredth, the z-scores for each of the following vacation expense amounts.
a. $197 per day.
b. $277 per day.
c. $310 per day.