[填空题]
Calculate the total w;ax :3 gllu+g urnmswbo b)1zu*-.)fqajnard*xk1 0bi 8 )h*pqter vapor pressure in the air on the following two days:
h r 0i*napbd)*1kj8qx (a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%; Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%. Pa