Question: Who is the second runner up when Janina San Miguel won binibining pilipinas-world?
Schema: create table table_1825751_4 (second_runner_up varchar, binibining_pilipinas_world varchar, PRIMARY KEY (second_runner_up))
SQL: select count(second_runner_up) from table_1825751_4 where binibining_pilipinas_world = "janina san miguel"