Hi,

A rectangular block of dimensions 6m×4m×2m and density 1.5gm/cc is lying on horizontal ground with the face of largest area in contact with the ground.

The volume of block is 6*2*4=48 cu.m.

The density is 1.5 gm/cc.

So the mass is : 1.5*48*1000 kg

Here the work done is in the form of potential eneegy :

So, work done is mgh = 1.5*48*1000*10*2(smallest are in contact)

=1440 kJ.

Hope this helps!