In a gymnasium with dimensions 20*15*4 m^3, air exchange is 2 times per hour in October. The outdoor climate is 5-10 degrees and indoors 20 degrees. The athletes emit 0.4 kg kg of water vapor per hour. The hall is ventilated at the start of training

a) What is the relative humidity after 1 hour with 50 athletes?

b) What temperature are the windows if dew forms after 30 minutes

c) Calculate the heat loss in KW without heat recovery

d) Calculate the heat loss with heat recovery 82% KW

e) Calculate the annual expected heat loss in kWh and MJ with an average air change of 0.5 times per hour and unchanged efficiency

f) Calculate the annual expected transmission heat loss kwH and MJ for the gymnasium with an average u value of 0.25 W/m^2K for a detached gymnasium. Ignore heat loss through the floor.