2000cm³.
The volume of any 3d shape is the length x height x width.
This case it is 25 x 10 x 8.
Density = 2 Volume = 4cm cubed
29 (final) - 25 (starting) = 4 which is your volume
Density is M / V
Mass is 8
8 / 4 = 2
The silly putty's density is 2
Displacement x would be in terms of length, while t would be in terms of time.
Therefore the equation would have units of:
length = (b)*time^2
b = length/(time^2)
Therefore, the units of the constant b should be in length per time^2 (for example, in m/s^2, such as in acceleration).