Who was the alderman of the legislative district where case No. JB103470 took place? Give the full name.
case No. JB103470 refers to case_number = 'JB103470'; full name refers to alderman_first_name, alderman_last_name
SELECT T1.alderman_first_name, T1.alderman_last_name FROM Ward AS T1 INNER JOIN Crime AS T2 ON T1.ward_no = T2.ward_no WHERE T2.case_number = 'JB103470'