Which of the following will have the highest pressure difference between the surface and 6 inches below the surface?

The pressure difference between the surface and a point below the surface of a fluid is determined by the depth of the fluid column and the density of the fluid. The fundamental principle involved here is that pressure increases with depth according to the hydrostatic pressure equation, which states that pressure at a depth is given by ( P = \rho g h ), where ( \rho ) is the fluid density, ( g ) is the acceleration due to gravity, and ( h ) is the height (or depth) of the fluid column above the point in question.

In this situation, regardless of whether it's a vertical straw, an open tank, or a vertical pipe filled with water, the pressure difference at a specific depth (in this case, 6 inches) will be the same as long as the fluid is incompressible (like water) and of uniform density. The height of the fluid column above the 6-inch depth directly determines the pressure at that point, and since the column height is the same (6 inches) in each case regardless of the shape or diameter of the container, the pressure difference will not vary among the three options presented.

Thus, the assertion that none of the conditions lead to a different pressure difference at 6