2x+4(7−x) HELP PLEASE IM DEPERAT

Someone answer this check out the image!

For the following geometric sequence, find the recursive formula. {-80, 20, -5, } i need : ')

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?