An IT infrastructure manager is reviewing his company's computer assets, particularly the mean time to failure $($MTTF$)$ of the PC and server hard drives. The manufacturer of the hard drives typically used in the company states that the MTTF is approximately $11$ years. Because servers and some high$-$priority workstations must operate continuously except for brief periods of maintenance, how many hours, on average, can these hard drives be expected to operate before failure?