"fertiliser"	"yield"
"1"	"A"	75
"2"	"A"	70
"3"	"A"	66
"4"	"A"	69
"5"	"B"	74
"6"	"B"	78
"7"	"B"	72
"8"	"B"	68
"9"	"C"	60
"10"	"C"	64
"11"	"C"	65
"12"	"C"	55
