Situation $2$: A $5m$ long cantilever beam $280mm600mm$ carries a uniformly distributed dead load of $4k\frac{N}{m}$

$($including beam weight$)$ and a concentrated live load of $5kN$ at the free end. The beam is pretensioned with $12$

diameter strands causing a final prestressing force of $600kN.$

Which of the following most nearly gives the resulting stress at the bottom fiber at the free end if the

prestressing strands are located at the neutral axis of the beam?