$a)4d{m}^3=4\cdot 1d{m}^3=4\cdot 1000c{m}^3=4000c{m}^3$

$b)11d{m}^3=11\cdot 1d{m}^3=11\cdot 1000c{m}^3=11000c{m}^3$

$c)0,2d{m}^3=0,2\cdot 1d{m}^3=0,2\cdot 1000c{m}^3=200c{m}^3$

$d)1,2d{m}^3=1,2\cdot 1d{m}^3=1,2\cdot 1000c{m}^3=1200c{m}^3$