$V=30\text{cm}\cdot 10\text{cm}\cdot 15\text{cm}=4500{\text{cm}}^3$  

$a)m=4500{\text{cm}}^3\cdot 19,3\frac{\text{g}}{{\text{cm}}^3}=86850\text{g}=86,85\text{kg}$ $a)m=4500{\text{cm}}^3\cdot 19,3\frac{\text{g}}{{\text{cm}}^3}=86850\text{g}=86,85\text{kg}$  

$b)m=4500{\text{cm}}^3\cdot 0,021\frac{\text{kg}}{{\text{cm}}^3}=94,5\text{kg}$  

$c)V=4500{\text{cm}}^3=4500\cdot 1{\text{cm}}^3=4500\cdot {\left(0,01\text{m}\right)}^3=4500\cdot 0,000001{\text{m}}^3=0,0045{\text{m}}^3$  

$m=0,0045{\text{m}}^3\cdot 10500\frac{\text{kg}}{{\text{m}}^3}=47,25\text{kg}$  

$d)V=0,0045{\text{m}}^3\cdot 1140000\frac{\text{dag}}{{\text{m}}^3}=5130\text{dag}=51,3\text{kg}$