Why do African Americans pronounce the work "ask" as "axe"?

Is there something anatomically in the mouthes of African Americans the prevent them from pronounce "ask" correctly. I wish I could ask some of them to pronounce "task", "flask", "mask", "gasket", "ski" , "skit", "skim". I wonder how those words would be pronounced. Maybe someone on GAG is a speech therapist and can answer this.

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+1 y
Should read "pronounce the word "ask"
Why do African Americans pronounce the work "ask" as "axe"?
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