tech = [[2    0    0  0   0]     #plough.f-plow-6
        [3    3    0  0   0]     #plough.f-plow-3
        [0    0    45 0   0]     #plough.f-plow-1
        [0.6  0    0  0   0]     #disce.harrow-o-d
        [0    1    0  0   0]     #disce.harrow-s-t
        [0    0    6  0   0]     #disce.harrow-s
        [0    1.6  0  0   0]     #harrow.harrow-s-t