Does the circle with center c(0,5) that passes through the point a(6,2) also pass through the point b(-3,11)?

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?