a,3781132.280,518657.121,400,3781174.635,518623.879,456
b,3782597.579,520987.447,654,3782639.903,520954.174,564
c,3781923.614,518501.500,658,3781965.957,518468.263,654
*****************************
1,3781916.999,520855.911,254
2,3782580.436,518282.323,236
3,3781132.280,518657.121,654
4,3780576.686,520035.901354