"x1"	"x2"	"y"	"x1x2"
0.6	200	90.6	120
0.6	250	82.7	150
0.6	400	58.7	240
0.6	500	43.2	300
0.6	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