A certain cube floating in a bucket of water has between 70 and 85 percent of its volume below the surface of the water. If between 8 and 20 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  Answers.
A) 4
B) 5
C) 7
D) 8
E) 9

Rationale: "if sides are 7 , vol = 7 ^ 3 = 343 70 % = 240.1 , 85 % = 291.55 so vol above water , between 102.9 and 51.45 - - > too big if side are 4 , vol = 64 70 % = 44.8 , 85 % = 54.4 vol above water between 19.2 and 9.6 so 4 should be the answer . check option c , if sides are 5 , vol = 125 70 % = 87.5 , . 85 % = 106.25 vol above water between 18.75 - 37.5 ( sides are 4 cubic centimeters ) a"
Answer: A