Which piece relation defines a function ?

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

Find the unit rate for: 75% high-fiber chimp food to 25% high -protein chimp food.

What is the solution to the division problem below x3+x2-11x+4/x+4