0.1 km
2cm/year * 5000 yrs = 10000 cm
1cm= .01 m
1km = 1000 m
so the answer is 0.1 km
Answer:

Explanation:
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In this case, since the percent water is computed by dividing the amount of water by the total mass of the hydrate; we infer we first need the molar mass of water and that of the hydrate as shown below:

Thus, the percent water is:

So we plug in to obtain:

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