Consider a polished, unnotched specimen made 2024-T4 drawn rod loaded in the longitudinal direction (see page MH3-112). The specimen is subjected to a fatigue cycle with a minimum stress of 10 ksi and is desired to have a life of 105 cycles to failure. Determine the corresponding fatigue cycle maximum stress according to the equivalent stress model. Repeat this calculation if the minimum stress is increased to 20 ksi.