A room measures 1.0 m by 3.8 m by 5.9 m. The heating and air-conditioning ducts to and from the room are circular with diameter 0.30 m and all the air in the room is to be exchanged every 15 min.
(a) What is the average flow rate? (answer in m3/s)
(b) What is the necessary flow speed in the duct? (Assume that the density of the air is constant.) (answer in m/s)