题目2. 若 |} (a)_(1)& (a)_(2)& (a)_(3) (b)_(1)& (b)_(2)& (b)_(3) (c)_(1)& (c)_(2)& (c)_(3) | .-|||-A. 30m B. -15m C.6m D. -6m题目解答答案D