Relative humidity is given by (where pv = Partial pressure of water vapour, pb = Barometric pressure, ps = Pressure of saturated air, pd = Pressure at dry bulb temperature, pw = Saturation pressure corresponding to wet bulb temperature, and μ = Degree of saturation)

A. 0.622 Pv / (Pb - Pv)

B. μ/[1 - (1 - μ) (Ps/Pb)]

C. [Pv (Pb - Pd)]/ [Pd (Pb - Pv)]

D. None of these

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