Answer:
D
Explanation:
Someone's perception can be all of these things. the way one person sees something is different than the way someone standing right beside them sees it.
Answer:

Explanation:
Hello!
In this case, considering that the mass of hydrazine is missing, we can assume it is 130.0 g (a problem found on ethernet). In such a way, since we need a mass-mole-atoms relationship by which we can compute moles of hydrazine given its molar mass (32.06 g/mol), then the moles of hydrogen considering one mole of hydrazine has four moles of hydrogen and one mole of hydrogen has 6.022x10²³ atoms (Avogadro's number); therefore, we proceed as shown below:

Notice 130.0 g has four significant figures, therefore the result is displayed with four as well.
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You may feel cold when you touch certain kinds of matter because some matter gives off cold air. I’m NOT SURE
Answer:
Explanation:
The whole sample is 269
%copper = 127/269 * 100 = 47.2%
%chlorine = 142/269 * 100 = 52.8%
That's all you are asking. Is there more?
Explanation:
Bacteria play a key role in the nitrogen cycle.
Nitrogen-fixing microorganisms capture atmospheric nitrogen by converting it to ammonia— NH3start text, N, H, end text, start subscript, 3, end subscript—which can be taken up by plants and used to make organic molecules.