; (B) an equitable geographic distribution of such grants, including an equitable distribution between urban and rural areas; and (C) that grants are used to develop or improve remedial education programs— (i) for a range of types and sizes of institutions of higher education; and (ii) for each of the models described in subsection (c) to ensure adequate sample sizes to enable statistical comparisons within and among such models; and (2) give preference to eligible entities that primarily serve low-income students. (e) Fiscal requirements (1) Supplement not supplant A grant awarded under this section shall be used to supplement, not supplant, funds that would otherwise be used to carry out the activities described in this section. (2) Matching funds (A) In general Subject to subparagraph (B), an eligible entity that receives a grant under this section shall provide, from non-Federal sources, an amount equal to 10 percent of the amount of the grant for the cost of activities assisted under the grant. (B) Exceptions The requirements of subparagraph (A) shall not apply to— (i) Tribal Colleges or Universities