PLEASE DO NOT ANSWER WITH THE SAME FROM CHEGG

Barnett, a baggage loader for U.S. Airways (USA), injured his back while loading an inordinately heavy suitcase. He was diagnosed with a permanently slipped disk and recurring back spasms. His condition is permanent and he is considered disabled under the ADA. Upon returning to work, USA offered to reassign him to luggage deliverer, where he would drive the baggage carts from plane to plane, no lifting required. Barnett instead wanted a position in the mailroom. USA denied his request because the company operates on a strict seniority system for filling vacancies.

Does Barnett have a cause of action under the ADA?

Why or why not? Has USA fulfilled its duty of reasonable accommodation?