piecewise[{{1000, 0<=x<=2},{-1000/6x+1000*(4/3), 2<x<=8}}],piecewise[{{1000, 0<=x<=2},{-1000/5x+1000*(7/5), 2<x<=7}}],piecewise[{{1000, 0<=x<=1},{-1000/4x+1250, 1<x<=5}}]