She deposited $16,000 at 4% and $32,000 at 4.5%
Start with

Since square root and square are two opposite operations, we have

So, we have

Use the rule
to conclude

If the temperature changed from 17 degree F to -7 , the change was
17+7=24 degrees F
the average change was 24/12=2 , 2 degrees per hour
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