I believe the answer is: <span> preservation of evidence.
</span><span> preservation of evidence is critically important because the genetic Trace or fingerprints that left on the evidence could be easily erased.
When such evidence is erased, the justice department wouldn't have sufficient proof when they are prosecuting the suspects.
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Their annual income is below 23,000 dollars
Happiness could be anything. It could be the every day things you do that makes you grateful. It could be the fact the you have shelter over your head when you go home or the shoes you have on. Happiness is how you feel towards something and how it makes you feel.