; (D) an explanation of how the statutory and regulatory flexibility provided to an institution participating as an experimental site is expected to increase student success, as required under subsection (a); and (E) a copy of the evaluation plan developed under subsection (d). (f) Duration (1) In general Except as provided in paragraph (2), the duration of an experiment under this section shall not exceed a period of four years beginning with the first award year for which Federal financial aid is disbursed to students participating in the experiment. (2) Extension The Secretary may extend an experiment for up to two years beyond the four-year period specified in paragraph (1) on a case-by-case basis. (g) Determination of success For the purposes of subsection (a), the Secretary shall make a determination of success regarding an institution’s participation as an experimental site based on— (1) whether, and to what extent, student outcomes improve as a direct result of the experiment; (2) whether the experimental site improves the delivery of services to, or otherwise benefitted, students