'x1','x2','y','x1x2'
.6,200,90.6,120
.6,250,82.7,150
.6,400,58.7,240
.6,500,43.2,300
.6,600,25,360
1,200,127.1,200
1,250,112.3,250
1,400,19.6,400
1,500,17.8,500
1,600,9.1,600
2.6,200,53.1,520
2.6,250,52,650
2.6,400,43.4,1040
2.6,500,42.4,1300
2.6,600,31.6,1560
2.8,200,40.9,560
2.8,250,37.9,700
2.8,400,27.5,1120
2.8,500,27.3,1400
2.8,600,19,1680