It gained popularity as a college admissions exam in the central and midwestern US
I don't know where nacl is from originally, but acc/ to this, it might (or must have) been in the central or Midwestern U.S.
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since the SAT was only used by selective institutions in the northeast
Well, I did not attend the selective schools in the northeast. I was born there, spent most of my life there and attended many years of school there.
I was never offered an option between SAT and ACT, never.
Honestly, I never heard of the ACT test.
Grateful to you for the explanation.
Thank-you.