Answer:
The addition or subtraction of an electron and change ions to have a positive or negative charge. So, if and ion with an equal amount of protons and electrons gains an electron, it becomes negatively charged.
Explanation:
The option that is not a basic method used by ecologists to study the living world is B. animal training, whereas they do experimenting, modeling, and observing as part of their study of the living world.
There are animal trainers whose job it is to train animals - ecologists don't have to do that.
What numbers?......
Explaination:
Volume=Mass/Density
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