How many projections should you sketch for any given object? only as many as you need to fully communicate all features
up to six projections
three; the bottom, top, and one side
four; the bottom, top, and both sides

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.