A solid square rod is cantilevered at one end. The rod is 1 m long and supports a completely reversing transverse load at the other end of ±1.5 kN. The material is AISI 1080 hot-rolled steel. If the rod must support this load for 4 × 104 cycles with a design factor of 1.5, what dimension should the square cross section have? Neglect any stress concentrations at the support end.