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oksian1 [2.3K]
3 years ago
13

A toxic radioactive substance with a density of 9 milligrams per square centimeter is detected in the ventilating ducts of a nuc

lear processing building that was used 45 years ago if the half life of the substance is 20 years what was the density of the substance when it was deposited 45 years ago
Mathematics
1 answer:
Crank3 years ago
6 0

  Think about what a half-life means as a table.

years amount Left

20 1/2

40 1/4

60 1/8

80 1/16

Starting at t = 0, the amount left (or density) = (1/2)^(t/20)

For t =35, the decay factor = .297

Since you need to work backwards, divide by that factor.  6 / .297 = 20.18 mg per sq cm

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Answer:

Not enough information provided

Step-by-step explanation:

To find the difference between one terabyte and the storage available to the other mediums, we would need to know the storage available to those mediums.  They can all have potentially different amounts of storage space, so we have no way to answer that part of the question.

We can however find out how many bits her computer has.  There are two lines of thought  to follow though.  kilo, mega, giga etc each generally note a multiple of 1000 in common terms.  In computer tech though, the number 1024, or 2¹⁰, is often used instead.

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If you want to express the latter as a power of ten for proper scientific notation, then it would be 8.796093022208 × 10¹² - a rather useless way of expressing it, but just to cover all bases.

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Answer:

Step-by-step explanation:

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