某水源地面积A=20km2,潜水层平均给水度μ为0.1,其年侧向入流量为1×106m3,年侧向出流量为0.8×106m3,年垂直补给量为0.5×106m3,年内地下水位允许变幅△h=6m,则计算区的允许开采量应为( )106m3
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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