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The Great War Exhibition When: Sun 10 Jan, 9:00 am- 6:00 pm   Mon 11 Jan, 9:00 am- 6:00 pm Where: Dominion Museum Building, 15 Buckle Street, Wellington Restrictions: All Ages Ticket Information: Admission Free   The journey i rich in personal stories which tell of the great experience of the battlefields and the hardships at     home during wear-time New Zealand. The visitors will experience the desperate horrors and the victories of the human spirit that were part of the Great War. Kaipara Coast Plants & Sculpture Gardens When: Sun 10 Jan, 9:00 am- 5:00 pm   Mon 11 Jan, 9:00 a3．如图，∠AOB=90°，C在OB的延长线上，D为⊙O上一点，∠BAD=∠BDC．（1）求证：CD是⊙O的切线；（2）若⊙O的半径为1，且OB=BC．，求四边形AOBD的面积．