ducem DN II CB ⇒DC=AN
ducem CN II AD ⇒DC=NB
rezulta ca AB=2CD
triunghiul CNB echilateral isoscel CN=CB=NB
CM=120√3 dam
MB=120√3/2=60√3
notam L=CB
L²=(120√3)²+(L/2)²=43200+L²/4
L²-L²/4=43200
3L²/4=43200
L²=57600
L=240
P=240+240+240+2x240=5x240=1200 dam
1dam=0,01 km
1200 dam x0,01=12 km