3)
A.0,0253hm+5dam+340cm+890mm=
=2,53m+50m+3,4m+0,89m
=56,82m
B.560cm²+0,025m²+47690mm²=
=0,056m²+0,025m²+0,04769m²
=0,12869m²
D.450dL+78034mL=
=45L+78L
=123L
C.2L+12dm³+0,01m³=
=2dm³+12dm³+0,01m³
=2dm³+12dm³+10dm³
=24dm³=0,024m³
E.2h30min45s-1h45min55s=
=44min50s
=2.690s