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Here's your shmoop du jour, brought to you by diamonds.

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They're just carbon that's really uptight.

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Which of the following best describes the change in atmospheric 14C after 1965?

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And here are your potential answers...

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We've done this several times already...which figure should we use to solve the question?

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We're looking for the figure that shows changes in amounts of carbon-14...so we're definitely

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looking at figure 1.

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The question says "after 1965." So let's start by locating 1965 on both curves.

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Next, we'll notice that after 1965, both lines start sloping downwards.

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That means the change in 14C is decreasing, not increasing.

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We can rule out choices (C) and (D) because both say increase. Now, all we have to do

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is decide whether the trends are decreasing linearly or exponentially.

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Linear means in a straight line, but neither of those curves look straight to us.

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That is, after all, the definition of a curve, right?

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That means that the change must be declining exponentially!

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The correct answer is (B).

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