L=2w l x w=4 in² V=lx wx H=1536in^3, so H= 1536 /lxw=384 and l x (l/2) xH =1536 l²/2 x384 =1536, implies I=sqrt(1536/192) so I= 2.82 and when l = 2.82=2w we can get w=I/2=2.82/2=1.41 finally the original dimensions of the piece of metal were I=2.82, w=1.41 and H= 384 (the uniti is inch)