The al2o3 crystal structure (corundum) consists of an hcp arrangement of o2- ions; the al3+ ions occupy octahedral positions. what fraction of the available octahedral positions are filled with al3+ ions? in corundum, the al3+ ions do not fill the tetrahedral positions.

a corroding iron, if that's one of your choices

you did not give any options thus this is the best answer i can give to you with this little information you have given

> they are both natural and not man made

> they can be tracked and predicted by the right tools

-love shrooms

the answer is yes

it has kinetic energy

reason

an object has kinetic energy when you stop the force carrying it, the object will stay in motion.

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