You are on the island of knights and knaves. knights always tell the truth, and knaves always lie. suppose you meet two people: a and b. can you determine their identities if a says “at least one of us is a knave” and b says nothing?

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?