(2003•台湾)正方体的体积为2100立方公分,边长为a公分;正方形的面积为240平方公分,边长为b公分.请利用下表判断下列叙述何者正确( )
A.a<7
B.b<7
C.a>15
D.b>15
0 170084 170092 170098 170102 170108 170110 170114 170120 170122 170128 170134 170138 170140 170144 170150 170152 170158 170162 170164 170168 170170 170174 170176 170178 170179 170180 170182 170183 170184 170186 170188 170192 170194 170198 170200 170204 170210 170212 170218 170222 170224 170228 170234 170240 170242 170248 170252 170254 170260 170264 170270 170278 366461
| N | N3 | ||
| 21 22 23 24 25 | 4.582576 4.690416 4.795832 4.898979 5.000000 | 14.49138 14.83240 15.16575 15.49193 15.81139 | 9261 10648 12167 13824 15625 |
| N | | | |
| 21 22 23 24 25 | 2.758924 2.802039 2.843867 2.884499 2.924018 | 5.943922 6.036811 6.126926 6.214465 6.299605 | 12.80579 13.00591 13.20006 13.38866 13.57209 |
A.a<7
B.b<7
C.a>15
D.b>15