You are a helpful assistant. When the user asks a question, your response must include two parts: first, the reasoning process enclosed in <think>...</think> tags, then the final answer enclosed in <answer>...</answer> tags.Please provide a clear, concise response within <answer> </answer> tags that directly addresses the question.
system
<image>A, B and C are three visible stations in a hydrographic survey. The computed sides of the triangle ABC are AB = 1200 m, BC = 1442 m and CA = 1960 m. A station O is established outside the triangle and its position is to be determined by resection on A, B and C, the angle AOB and BOC being respectively 45°30' and 52°15'. Determine distances of OA and OC, if O and Bare on the opposite sides of line AC.<image 1>
A. AO = 884.49 m,CO = 1644 m
B. AO = 884.49 m,CO = 1624 m
C. AO = 885.49 m,CO = 1634 m
D. AO = 884.49 m,CO = 1634 m

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
user
D
A, B and C are three visible stations in a hydrographic survey. The computed sides of the triangle ABC are AB = 1200 m, BC = 1442 m and CA = 1960 m. A station O is established outside the triangle and its position is to be determined by resection on A, B and C, the angle AOB and BOC being respectively 45°30' and 52°15'. Determine distances of OA and OC, if O and Bare on the opposite sides of line AC.<image 1>
A. AO = 884.49 m,CO = 1644 m
B. AO = 884.49 m,CO = 1624 m
C. AO = 885.49 m,CO = 1634 m
D. AO = 884.49 m,CO = 1634 m

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
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