Răspuns:
eod +doc +cob=180
90+30+cob=180
cob=60
eod+doc++eoa=180
90+eoa+30=180
eoa=60
60+aob=180
aob=120
aoc=180
2. nob=noc=25 30'
2nob=51 grade=aoe
180=moe+eod+doc+con
180=25 30'+eod+90+25 30'
eod=180-90-51
eod=39 grade
aob=180-51
aob=129
boc=51
