$4($Marks $=15)[$Answer in the space provided, show important calculation steps$]$

A $1$ kg sample of moist air initially at a relative humidity of o $=60\%$ and a wet$-$bulb temperature

f Twb $=20"$C at $101$ kPa is cooled to a dry$-$bulb temperature of Tao$=10"$C$.$

Using the Psychrometric chart in the following page determine

$($a$)$ Initial dry$-$buib temperature $($Tao$),$ initial dew$-$point temperature $($Tam$),$ initial and final

humidity ratio $($w$1,$ wz$),$ and initial and final enthalpy $($hr$,$ hz$).$

The amount of water vapor that condenses, in