The most exact answer is 78.4J also in this kind of options we can say answer "d"
Because Na⁺ ion lacks an electron and O²⁻ has two extra electrons extra, to balance the charge, we need 2 Na⁺ ions.
All ions, atoms and molecules want to get to the minimum energy state, and that state is when the ion, atom, or molecule is neutral, that's why all of them want to balance their charges.
I believe the correct answer would be kimberlite. Diamonds are usually found in pipes 50 to 200 m across made of kimberlite. It is an igneous rock that is known to contain traces of diamonds. It is named base on the town where it was discovered which is Kimberley, South Africa.
The statement that is a quantitative observation is that bird has four different colors on it (option B).
<h3>What is a quantitative research?</h3>
A quantitative research is a systematic scientific investigation of quantitative properties and phenomena and their relationships, using statistical methods.
A quantitative observation has to do with numbers or numeric analysis.
This suggests that the statement that is a quantitative observation is that bird has four different colors on it.
Learn more about quantitative observations at: brainly.com/question/1434538
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