The city water company wants to transport 1, 800 m3 of water per day to a plant from a reservoir 8 km away. The water surface elevation at the reservoir is 6 m above the entrance of the pipe, and the water surface in the holding tank is 1 m above the exit of the pipe. The pipe will be laid on a 1500 slope. What is· the minimum diameter of a concrete (good joints) pipe that may be used if the water temperature varies between 4°C and 20°C? Assume minor losses are negligible.