solution:
The quoted atomic mass on the Periodic Table is the WEIGHTED average of the individual isotopic masses. The higher the isotopic percentage, the MORE that isotope will contribute to the isotopic mass. For this reason, most masses that are quoted on the Table are non-integral.
By way of example we could look to the hydrogen atom. The VAST majority of hydrogen atoms (in this universe) are the protium isotope. i.e. 1H, whose nuclei contain JUST the defining proton. There is a smaller percentage (>1%) of hydrogen atoms WITH one NEUTRON in their nuclei to give the deuterium isotope. i.e. 2H, and because this is relatively cheap, and easily incorporated into a molecule, deuterium labelling is routinely used in analysis.
And there is even a smaller percentage of hydrogen atoms with TWO NEUTRONS in their nuclei, to give the tritium isotope. i.e. 3H. The weighted average of the isotopic percentages gives 
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Answer:
<h2>0.05 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula

where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have

We have the final answer as
<h3>0.05 moles</h3>
Hope this helps you
Answer:
Loss of biodiversity in the wetlands.
Explanation: Pollution can be defined as the emission of toxic, poisonous and harmful chemical substances which are capable of causing environmental degradation and contamination.
Nitrogen pollution enters Earth’s freshwater resources from a variety of human activities, including the use of fertilizers and pesticides in agriculture. This nitrogen pollution has a negative effect on plants and animals living in fresh water. Certain wetland plants, however, are able to purify the water and restore it to its non-polluted state.
Hence, what would most likely increase the negative effects of nitrogen pollution is a loss of biodiversity in the wetlands i.e the various species of animal and plants.