How have courts interpreted the meaning of the word "reasonable" in the context of disability legislation?

We must read a statute to give effect to each word in it, so that none are superfluous. See State v. Watkins, 939 F.2d 710, 715 (9th Cir. 1991). The word "reasonable" in 42 U.S.C. S 12112(b)(5)(A) must refer to something other than the effects of the difficulty or expense on the employer of providing an accommodation. The statute makes sense only if "reasonable" refers to the effects of the accommodation on the employee's ability reasonably to perform the essential functions of the job and does not include effects of difficulty or expense on the employer.