How to simplify it?

The answer is -1 because
First you have to make the denominators equal so
-2(e-3f) = 6f-2e so if you multiply -2 to the numerator and denominator the fraction has the same value.
Once the denominators are equal you can get rid of them so you are left with
-2+1= -1
Hope this helps :)

Answer

:we are told that every year the temperature rises by 0.08degrees Centigrade,

So the difference between margin of error and the increase is much higher

That is

0.15-0.08=0.07

But remember Margin of error=Critical value *Standard deviation of population

And it is a quantity that measures accuracy

So the counter argument is that this is still an increase and it should be considered.

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