A barometer measures the pressure of the atmosphere at different altitudes. Identify the location where the column of mercury is lowest in the barometer.
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Answer:
the mercury would be lowest at location 4.
Explanation: this is because pressure and altitudes have inverse relationship at the troposphere. higher altitude has lower pressure. also pressure at location 4 contribute to pressure at location 1. but pressure at location 1 do not contribute to pressure at location 4.