Plz answer 2 questions i will mark the brainlest and you will have more points

1: when is seawater the densest?

2: noah created a model of a glacier to explain how glaciers change the surface of earth. he froze two large blocks of ice. one block was pure water. the other was water mixed with sand and rocks. if noah rubs each block across a piece of tin foil to demonstrate the glacial movement, how will the blocks most likely behave?

a
the pure block will run smoothly across the foil, while the sand and rock filled block will make scratches and rips in the foil.

b
the pure block will make scratches and rips in the foil, while the sand and rock filled block will run smoothly across the foil.

c
both blocks will slide smoothly along the foil, leaving trails of water behind.

d
both blocks will scratch and rip the foil, carrying pieces of foil along their path.