Answer:
Joe will give some milk to Rita in exchange for cookies
Step-by-step explanation:
Both Joe and Rita want to trade cookies in exchange for milk. However, Joe is willing to trade 2 cookies for one ounce of milk while Rita is willing to trade 4 cookies for an additional ounce of milk.
The one who is willing to trade the greatest quantity of cookies is Rita and she's willing to trade 4 of them for an ounce of milk (which Joe is willing to trade too).
Therefore, the most possible escenario would be the one where Joe will give some milk to Rita in exchange for cookies since this way he gets more cookies and they both wanted one ounce of milk anyway.