A full 500L tank of water is being drained at a rate of 5L per minute into an empty tank. How long will it take for the tank to have the same amount of water? Please help and thank you very much

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?