• Brainly User
A cashier is correct because the article "an" is used before words starting with vowels(a,e,i,o,u) or with vowel sounds.The article "a" is used before consonants.
E.g- An elephant ( word starting with vowel )
       An honest boy ( work starting with vowel sound - honest )

And so in this case,(cashier) we will say - a cashier.

Hope it helped :)

Mark it best ^_^
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