Insufficiently heated = cold
Insulated electrical wire = cord
The middle of an apple = core
Additional items = more
A female equine = mare
An article of commerce = ware
An imperfection = wart
Hotter than temperate = warm
You have a very large number of generic plastic building blocks, each in the shape of a cube.
Think about how many cubes you would need in order to construct a giant cube with 16 small cubes along each edge?
If you were to then remove the outside layer, how many small cubes would you have removed?
The original large cube with 16 small cubes along each edge would required 16 x 16 x 16 = 4,096 small cubes.
Removing the outside layer would leave a large cube now with 14 small cubes along each edge (which requires 14 x 14 x 14 = 2,744 small cubes).
It isn't 15 small cubes because you're removing both ends of an edge.
Therefore you have removed 4,096 - 2,744 = 1,352 small cubes.