There are various levels of ecology that can be used to study organisms and their interactions with the environment. What type of ecologist would be likely to compare the numbers of Northern Sawwhet Owls that migrate through the Midwest as compared to the Northeast

I would need answer choices to make a definitive answer, but most likely a population ecologist or migration ecologist.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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