A lecture theatre is to be maintained at a temperature of $25\backslash$deg C dry bulb and $18\backslash$deg C wet bulb

temperature. The outdoor conditions is assumed to be $33\backslash$deg C dry bulb and $28\backslash$deg C wet bulb. The fresh

air accounts for $20\%$ of the total supply air. The sensible heat load is $88$ kW$.$ Air is supplied to the

lecture theatre at $13\backslash$deg C with $95\%$ relative humidity. Determine

$($a$)$ the humidity ratio$($w$),$ dry bulb and wet bulb temperatures of the mixing air

$($b$)$ the mass flow rate of supply air,

$($c$)$ the sensible heat ratio and

$($d$)$ the latent heat load,

Assumptions: specific heat capacity of air: $1\mathrm{.}00$kJ$/$kg$,$ leaving coil at $95\%$ saturation, air density: $1$kg$/$m$3$