See attached image:
p/ρg + V^2/2g + z = constant
head loss (major) = f * l/D * V^2/2g
The Attempt at a Solution
To use the energy equation while incorporating head loss, I need to determine the velocity in each section of pipe. The problem is I don't know how! I do know that the pressure drop from the tank to the atmosphere is equal to the pressure in the tank.