A large steel crankshaft $($KIC $=45$ MNm$-3/2)$ undergoes cyclic tensile $(225$ MPa$)$ and compressive $(60$MPa$)$ stressesduringuse. Prior to use, it was inspected using ultrasonic techniques, fromwhichthe largest surfacecrack wasfoundas$2\mathrm{.}5$mminlength.Forthissteel,the Paris Lawconstants areA$=1\mathrm{.}5$ x $10-12($m$/$M MNm$-3/2)$mpercycle$,$andm$=2\mathrm{.}5.$Calculatethe numberofcyclestofailure.TakeY$=1.$