Answer:
In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. A crystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice.
Explanation:
The number of people per square mile is the population density
Answer:
Maybe they could you know, just not thow trash in the river?
Explanation:
They could also use energy more efficiently, they could instal renewables which are like solar and wind, they could use energy that is clos to wherever they are instead of using one thats way far away
I'm not really sure but if this helps great, if it doesn't I'm sorry
Answer:
D
Explanation:
If NASA had constructed a Space Shuttle without knowing if it would be safe for its passengers, there could be many casualties. So they would test it beforehand using a model, to make sure that it will be safe and sturdy for when they build it.
