The goals of are to determine the work load at which systems performance begins to degrade and to identify and eliminate any issues that prevent the system from reaching its required system-level performance. user acceptance testing system testing volume testing integration testing

Joe pays ann to mow his lawn and ann mows vanna's lawn by mistake. vanna peers out her window and sees ann mowing, yet says nothing to ann about her mistake since vanna needs to have her lawn mowed. when ann approaches vanna for payment, vanna refuses, arguing that she never asked ann to mow her lawn. under these circumstances, ann can recover payment from vanna under: