Well when writing a CER first you need to state your claim after stating your claim you need to support your claim with evidence from your sources and after that you need to give reasons on how your evidence supports your claim
Set up the equation.
Since gravity and liquid densities are fixed (for the most part), the height of the liquid is the largest variable in the equation. The equation reads as Pfluid = ρgh, where ρ is the density of the liquid, g is the acceleration of gravity, and h is the height of the liquid (or depth of the fluid)
A) The data to support his hypothesis, so he should investigate if the same change happens in the density of solid water.
C. your core will be made of protons will be made of protons and neutrons while being surrounded by "shells" of electrons.
