某学生在数轴上标出了三个有理数:-2.5、1 和 -0.75。若将这三个数按从小到大的顺序排列,正确的结果是?
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根据正负数表示相反意义的量,温度上升记为正,下降记为负。两天的变化分别为+5℃和-3℃,总变化为+5 + (-3) = 2℃,因此答案是2。
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