Which one holds more a half-gallon milk jug or a 2-liter juice bottle

To find the correct answer to the given question, it is important to bring both the units to liter or gallon. Let us convert the half gallon milk to liter. We already know that
1 gallon = 3.785 liter
Then
1/2 gallon = 3.785/2 liter
                 = 1.89 liter
From the above deduction we can conclude that the 2 liter juice bottle will hold more.