Charlotte has 1000 small cubes, each side measuring 1 cm.He uses these cubes to make large cubes with sides 2 cm, 3 cm,4 cm and so on.

(a)What is the length of the side of the largest cube that he can make using 729 small cubes?

(b)Find the length of the side of a cube that he made using 729 cubes.

(c) He dismantles the cube from part (b) and arranged them in the shape of a square 1 cm high with no cubes left over.What is the length of the side of the square?