źródło:
PO KOLEI 1:A C D D B 2: D A B C F 3: B D A D C CD 3 5kWh= 5* 3600000J=18000000J=18 MJ 7,2 10 do 6 J= 7,2*1000000J= 7200000J=7200000/3600000=2kWh odp B C 4: C A D B
5: E D A C D(DIOPTRIA) 6: A B E D C