Determine the maximum load for a simply supported beam of $50$ mm diameter and $600$

mm span, centrally loaded, as the load cyclically varies from W to $3$W$.\backslash$sigma en $=350$ MPa, $\backslash$sigma yp

$=525$ MPa and $\backslash$sigma u $=700$ MPa. Design factor of safety is $1\mathrm{.}3.$