a)
14 cm^2 = 14*(10mm)^2=14*100mm^2=1400mm^2
a)
85 dm^2 = 85*(10cm)^2=85*100cm^2=8500cm^2
c)
5 m^2 = 5*(10dm)^2=5*100dm^2=500dm^2
d)
1a = 100m^2 => 1m^2=\frac{1}{100}a=0,01a
200 m^2 = 200*\frac{1}{100}a=2a
e)
1 ha = 10 000 m^2 , 1m^2=\frac{1}{10000}ha=0,0001ha
12 000 m^2= 12000*0,0001ha=1,2ha