Calculate the pipe diameter D in inches to 2 decimal places required to give the fluid velocity of 4 ft/sec in the following situation: The formula for the velocity is given by: velocity =Flow rate / Pipe Area And the flow rate = 21 gpm and the Pipe Area is calculated from its diameter in inches, 231 cubic inches = 1 gallon, 12 inches = 1 ft, and 60 sec = 1 minute