Please help me answer

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?

Which expression and diagram represent “renee biked four times as far this month as last month”?

Write the standard form of an equation with (see picture below)