Answer:
Around 100,i.e. 105
Explanation:
In the given cube
Length of the cube = 7 unit cells
Breadth of the cube = 3 unit cells
Height of the cube = 5 unit cells
Therefore the number of unit cubes required to make such big cube is nothing but the volume of the big cube = length*breadth*height
⇒Number of cubes used to make that big cube= 7*5*3
= 105
Hence, option D (around 100) is the correct answer