Any notice or filing required or permitted to be given to the Plan Administrator under this Plan shall be sufficient if in writing and hand-delivered, or sent by registered or certified mail, to the Bank’s main office. Such notice shall be deemed given as of the date of delivery or, if delivery is made by mail, as of the date shown on the postmark or the receipt for registration or certification. Any notice or filing required or permitted to be given to a Participant under this Plan shall be sufficient if in writing and hand-delivered, or sent by mail, to the last known address of the Participant.