A$65 coat is now on sale for $52. what percent dis count is given

Ineed with number 17 i don’t get it at alll

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

Explain how the quotient of powers was used to simplify this expression.