What begins to happen to radioactive uranium as soon as a mineral containing it crystallizes from magma?

Stage in which a typical star has completely stopped fusion

Amixture with the same composition throughout is!

1) describe the physical layout of the ocean floor ? 2) explain how the dumbo octopus swims differently than other octopus species and why this would be an advantage in the aphonic zone . 3) why are the types of organisms that live at each underwater hot vent so dramatically different ?