Answer:The describing adjective used for the sentence;" The friendly cashier greeted me at the store. "Is "Friendly"Adjectives are used to describe or modify nouns. (People, places, things, etc.) They may answer the questions; "What kind?", "How many?", "Which one?", and "How much?".For example: -Welcoming: Friendly and hospitable.-Pleasant: Agreeable and enjoyable.-Polite: Showing good manners and respect.-Kind: Considerate and generous.-Helpful: Willing to assist or make things easier.Therefore, Friendly was the adjective used to describe the cashier.