What is fatigue strength (i.e. S in the Figure above) in [MPa] at the cycles calculated in (a) for this aluminium alloy

A 2014-T6 aluminium rod (3.5 cm in diameter) is subjected to a repeated tension-compression load cycling along its axis at a frequency of 100 Hz. If the part must last approximately 278 hours before failure, calculate the maximum allowable load amplitude (in N).

400 300 200 tr, 0 103,1045 steel,40,80 70 60 50 a 10 2014-76 aluminum alloy I Red bens I 104 105 104 lot 10° Cycles to failure. N 109

1.Determine the total number of cycles during the time
2.What is fatigue strength (i.e. S in the Figure above) in [MPa] at the cycles calculated in (a) for this aluminium alloy
3.Calculate the maximum allowed load in [N]