Please help me find the answers for 13 and 15. Thank you.

Abby is preparing fruit punch for her party. she starts with a bowl filled with liquid that has 1/2 fruit juice and 1/2 sprite, but she decides it's too fruity. so she pours out 1/4 of the liquid, and then fills the bowl up again with sprite. what fraction of the punch is now sprite?

What is the ratio of the change in y-values to the change in x-values for this function? a) 1: 13 b) 2: 5 c) 5: 2 d) 13: 1

Ineed with number 6 , explain how to get 1978