Dont go by the 30mm !! USE the 16!!! A hot rolled AISI 1040 shaft made…

Dont go by the 30mm !! USE the 16!!!
A hot rolled AISI 1040 shaft made transmits a repeated torque of T=500Nm. The reliability is 50% and the part will be used at room temperature. Find the factor of safety at a section where the diameter is 30mm. Use Goodman criterion T=500Nm 16 mm