George and Maria recorded the number of books they read for a 4-week period. If x is the number of weeks and y is the number of books read, what is the rule for Maria's data? Please help I am confused on this question.

The distribution of a sample of the outside diameters of pvc pipes approximates a symmetrical, bell-shaped distribution. the arithmetic mean is 14.0 inches, and the standard deviation is 0.1 inches. about 68% of the outside diameters lie between what two amounts?