暑假时,湖南某同学去新疆探望在那里工作的爸爸,发现了一些有趣的事儿。完成下面小题。
1.他发现手表的时针指向九点时,夜幕才开始降临。他很纳闷,请你帮他找出其中的原因( )A.纬度位置差异的结果 | B.海拔差异的结果. |
C.经度位置差异的结果 | D.气候差异的结果 |
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A.防止水污染 | B.避免水分大量蒸发 | C.少占耕地 | D.节约成本 |
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同类型试题
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y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
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y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
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