In[]:=
Plot[Piecewise[{{4,0<=x<1/9},{3.25,1/9<=x<2/9},{2.5,2/9<=x<4/9},{1.75,4/9<=x<5/9},{1.5,5/9<=x<7/9},{1.25,7/9<=x<8/9},{1,8/9<=x<1},{0,x=1}}],{x,0,1},PlotRange->{-1,4},AxesLabel->{"Length","Axial Stress Normalized w.r.t Weight"},Prolog->{Red,Thickness[0.005],Line[{{1,1},{1,0}}]}]
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