what is relative humidity

2 answers

From Google:

relative humidity: the amount of water vapor present in air expressed as a percentage of the amount needed for saturation at the same temperature.
Answers For 2022:
1.B. Humidity Can Be Measured Using g/m^3, While Relative Humidity Is Measured As A Percentage.

2.C. The Relative Humidity Is 100%, So Condensation Occurs.

3.B The Temperature Fell Overnight, And Colder Air Can Hold
Less Water Vapor.

4.B. No, As This Would Mean That The Air Holds More Water Vapor Than It Can.
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