what is the minimum total cost of a hospital with % hemoglobin a1c in 2105?
select min(t1.c1) from ( select sum(cost.cost) as c1 from cost where cost.hadm_id in ( select labevents.hadm_id from labevents where labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = '% hemoglobin a1c' ) ) and strftime('%y',cost.chargetime) = '2105' group by cost.hadm_id ) as t1