OPINION — AG — A BOARD OF EDUCATION CANNOT LEGALLY BUY MATERIALS AND SUPPLIES FROM A BUSINESS FIRM WHICH EMPLOYS REGULARLY ONE OF THE MEMBERS OF SUCH BOARD OF EDUCATION, REGARDLESS OF WHETHER THE BOARD MEMBER OR A MEMBER OF HIS FAMILY OWNS ANY SUBSTANTIAL INTEREST IN THE BUSINESS. (CONFLICT OF INTEREST) CITE: 62 O.S.H. 371, 70 O.S.H. 4-29 (J. H. JOHNSON)