A small laboratory experiment consists of a single fan in a circular duct which draws air from the room. The room is sufficiently large that the air can be assumed to be at rest. The air is drawn in through a well rounded inlet (assume a loss factor of 0.05) and is driven through the ducting which has 3 90 bends, each with a loss factor of 0.3, before being exhausted back to the room again. The ducting has a total length of 6m and the duct diameter is 0.2m. The ducting has a friction factor of 0.02. If the flow velocity in the ducting is 47m/s, how much power (in kilowatts) does the fan add to the air. (The density of air is 1.225kg/m)