If the height was 10, then the volume of the cube would be 1000 because you find volume you must multiply the length*width*height and the value of those three is 10.
Now since volume is 1000 and the volume of a 2in cube is 8 (again, lwh=V) you can divide 1000 by 8 and you would get 125. So that means 125 2in cubes can fit inside the bigger cube.
If the volume of this cube were 750in^3 and you had to find the height, you would use the Volume formula again:
l*w*h=V
10*10*h=750
20h=750
((divide both sides of the equation by 20 to find the value of h))
h=37.5
If the surface area of the cube were 680in^2 then you would use the surface area formula to find the value of h:
(2(lw))+(2(lh))+(2(wh))=A
(2(10*10))+(2(10h))+(2(10h))=680
200+20h+20h=680
subtract 200 from both sides of the equation:
40h=480
divide both sides by 40 to get the value of h:
h=12