ha ar
1km^ 2 hm^2 dam^2 m^2 dm^2 cm^2 mm^2
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10^2 10^2 10^2 10^2 10^2 10^2
ex. 2hm^2 =2*10^2*2 =2*10^4 =20000dam^2
2hm^2 =2*10^2*4 =2*10^8 =200000000cm^2
unitatile mari se transorma in unitati mici prin inmultire cu 10^2*n
'' mici '' ''' '' '' '' mari '' impartire la 10^2 *n