In what order do the following occur from the surface to the bottom of an oil well?

When drilling an oil well, a borehole is drilled through the earth's crust into the subsurface layers. The layers of earth are made up of different materials such as rock, sand, and water. These layers can also contain different substances, such as oil and gas. In an oil well, the first substance encountered is gas, which rises to the top because it is lighter than the other substances. This is followed by oil, which is less dense than water and, therefore, floats on top of the water layer. The last substance to be encountered is water, which is the heaviest and thus sinks to the bottom of the well. Therefore, the correct order from the surface to the bottom of an oil well is: gas, oil, water.