题目

---Yesterday, my father bought me a new mobile phone as a present, but I don’t know how to use it.        ---Why not read the _______first before using it? A. expressions   B. contributions  C. advertisements  D. instructions 答案：D写出下面各组数的最大公因数和最小公倍数．10和914和4212和9最大公因数：______最大公因数：______最大公因数：______最小公倍数：______最小公倍数：______最小公倍数：______．