The steel bar with the geometry has an axial fluctuating load applied from -5000 lbf to 12000 lbf. The bar has a hole with a 0.25 inch diameter, is 0.25 inches thick, a fillet radii of 0.175 inches, and a notch sensitivity factor q = 0.95. The fully adjusted endurance limit of the bar is 40 ksi, the bar has an ultimate strength of 185 ksi, and a fatigue strength fraction f = 0.78. Using the Goodman criteria, determine the most conservative N to design to, where N is the life of the bar in terms of cycles to failure. a. Less than 1 cycle
b. 1 to 5 cycles
c. 17000 to 29000 cycles
d. 40000 to 60000 cycles
e. 63000 to 80000 cycles
f. 5 to 6 million cycles
g. Infinite life