正方体表面积 S = 6 a^2 = 72 cm^2
a = 2 sqrt(3) cm
正方体体积是 V = a^3 = 24 sqrt(3) cm^3
长方体体积是3V = 72 sqrt(3) cm^3 = 124.71 立方厘米那长方体原表面积呢长方体原表面积 = 3S - 4a^2 = 72*3 - 4 * 12 = 216 - 48 = 168 cm^2