Electrons are negatively charged particles. Like charges repel one another, so electron pairs will want to be as far apart from each other as possible. Thus, the answer here would be A.
Answer:
magnesium atom
The most common and stable type of magnesium atom found in nature has 12 protons, 12 neutrons, and 12 electrons
Check dams shouldn't be more than 2-3 feet high. The center of it should be at least six inches lower than the edges. They might kill grass linings in channels if water stays high or sediment load is great. That criteria induces a weir effect, which makes water surface levels go upstream for some, if not all flow conditions.
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