A certain cube floating in a bucket of water has between 80 and 90 percent of its volume below the surface of the water. If between 6 and 13 cubic centimeters of the cube's volume is above the surface of the water, then the length of a side of the cube is approximately	Choose the correct choice from the following options:
A) 4  B) 5  C) 7  D) 8  E) 9

Rationale: "if sides are 7 , vol = 7 ^ 3 = 343 80 % = 274.4 , 90 % = 308.7 so vol above water , between 68.6 and 34.3 - - > too big if side are 4 , vol = 64 80 % = 51.2 , 90 % = 57.6 vol above water between 12.8 and 6.4 so 4 should be the answer . check option c , if sides are 5 , vol = 125 80 % = 100 , . 90 % = 112.5 vol above water between 12.5 - 25 ( sides are 4 cubic centimeters ) a"
Answer: A