What is the remainder in the synthetic division problem below?

Can someone me with these two circle theorem questions asap?

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?

240 seventh graders and two-thirds of the students participate in after-school activities how many students participate in after-school activities