Răspuns :
17 km^2 (dam^2) = 17×10^4=170000dam^2
4,2dm^2 (mm^2)=4,2×10^4=42000mm ^2
25m^2 (dam^2)=25:10^2=0,25dam^2
39000mm^2 (dm^2)=39000÷10^4=3,9dm^2
4,2dm^2 (mm^2)=4,2×10^4=42000mm ^2
25m^2 (dam^2)=25:10^2=0,25dam^2
39000mm^2 (dm^2)=39000÷10^4=3,9dm^2