The gauge is shown in the test position. In the rest position the plunger shall be above plane V.

图中所示量规处于检验状态。当静止状态时，柱塞应在V面以上。

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In London, Picarro will place analyzers on the ground around the city as well as one on a bus to measure carbon emissions at road level and another on a plane to gauge emissions at higher altitudes.

FORBES: Going For The Green: Measuring The London Olympics' Carbon Footprint