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> 热气球充满气体后升空的平均速度是1m/s，到达一定的高度后立即返回，下降的平均速度为3m/s，则热气球在全过程中的平均速度是 A.2m/s B.2.5m/s C.1.5 m/s D.无法计算

问题：

发布时间：2024-09-11

热气球充满气体后升空的平均速度是1m/s，到达一定的高度后立即返回，下降的平均速度为3m/s，则热气球在全过程中的平均速度是

A.2m/s
B.2.5m/s
C.1.5 m/s
D.无法计算

参考答案：

提问用户：p2***9yA

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