A) 216 = 2x2x2x3x3x3,
216 form 2 tribplet so it a perfect cube.
B) 128 = (2x2x2)x(2x2x2)x2
128 is not a perfect cube
c) 1000 = (2x2x2)(5x5x5) So, it is a perfect cube
D) 100 = (2x2)(5x5)
100 is not a perfect cube
E) 46656 = (2x2x2)x(2x2x2)x(3x3x3)x(3x3x3)
46656 is a perfect cube.