A. "Sergeant, erect that flagpole."
In other words, if the sergeant knows how to do it, then there's no need for you risk, as an officer, making a fool of yourself in front of the enlisted men by issuing some cockamamie order about how to erect the flagpole. If the sergeant doesn't know, well, he'll probably order the corporal to do it, and so forth down the chain of command to Pvt. Beetle Bailey, but by the time the problem comes back up to you, it will be well-established that everyone is as clueless as you are.
John Derbyshire adds:
In the British Army, it would have been:
OFFICER ON PARADE! ERECTING FLAGPOLE BY NUMBERS! -- FLAGPOLE, E-E-E- WAIT FOR IT! --- E-E-RECT! ONE!...
Bloody Yanks don't know the meaning of the word "discipline."