All notices, requests, and demands hereunder shall be in writing and (a) made to CMC at its address designated in writing by CMC and to Guarantor at its chief executive office set forth in writing to CMC, or to such other address as either party may designate by written notice to the other in accordance with this provision; and (b) deemed to have been given or made: if delivered in person, immediately upon delivery; if by telex, telegram or facsimile transmission, immediately upon sending and upon confirmation of receipt; if by nationally recognized overnight courier service with instructions to deliver the next business day, one (1) business day after sending; and if by certified mail, return receipt requested, five (5) days after mailing.