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ZX-4606C5207F2025年9月美国A卷 · 第 21 题
2025年9月美国A卷 · 原库模块 2 · Q21 原库参考解析
A quadratic function gives the estimated length of daylight \( d(t) \), in hours, in a certain city t months after March 1, where \( 0\le t\le7 \) . According to the function, the estimated length of daylight is 12.66 hours 6 months after March 1 and the maximum estimated length of daylight is 13.91 hours 3.5 months after March 1. Based on this function, what is the estimated length of daylight, in hours, on March 1?
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