In a kitchen there are four containers that can hold different quantities of water, as shown in the figure below: Four containers of the same shape but different sizes are shown, arranged from the shortest to the longest. The following quantities are written below the containers. x minus 2 liters below the first, x liters below the second, x plus 2 liters below the third, and x plus 4 liters below the fourth. How many liters of water can the four containers hold in all? x4 + 4 2x + 4 x2+ 2x 4x + 4