The relative humidity on a day, when partial pressure of water vapour is 0.012×105 Pa at 12°C is ___? ( vapour pressure of water at12°C is 0.016×105 Pa )

Partial pressure of water vapour,Pw=0.012×105Pa Vapour pressure of water P=0.016×105 PaThe relative humidity at a given temperature is given by,= Partial pressureof water vapour  Vapour pressureof water =0.012×1050.016×105=0.75 or 75%